diff --git a/app/src/main/java/kr/co/vividnext/sodalive/extensions/StringExtensions.kt b/app/src/main/java/kr/co/vividnext/sodalive/extensions/StringExtensions.kt
index 81a4f216..8530fc22 100644
--- a/app/src/main/java/kr/co/vividnext/sodalive/extensions/StringExtensions.kt
+++ b/app/src/main/java/kr/co/vividnext/sodalive/extensions/StringExtensions.kt
@@ -12,8 +12,8 @@ import java.util.TimeZone
 fun String.convertDateFormat(
     from: String,
     to: String,
-    inputLocale: Locale = Locale.KOREAN,
-    outputLocale: Locale = Locale.KOREAN
+    inputLocale: Locale = Locale.getDefault(),
+    outputLocale: Locale = Locale.getDefault()
 ): String {
     val fromDateFormat = SimpleDateFormat(from, inputLocale)
     val toDateFormat = SimpleDateFormat(to, outputLocale)
diff --git a/app/src/main/java/kr/co/vividnext/sodalive/message/text/TextMessageDetailActivity.kt b/app/src/main/java/kr/co/vividnext/sodalive/message/text/TextMessageDetailActivity.kt
index 714bfa81..bdb15132 100644
--- a/app/src/main/java/kr/co/vividnext/sodalive/message/text/TextMessageDetailActivity.kt
+++ b/app/src/main/java/kr/co/vividnext/sodalive/message/text/TextMessageDetailActivity.kt
@@ -53,21 +53,24 @@ class TextMessageDetailActivity : BaseActivity<ActivityTextMessageDetailBinding>
 
         when {
             messageBox!! == MessageBox.RECEIVE.name -> {
-                binding.toolbar.tvBack.text = "받은 메시지 상세"
+                binding.toolbar.tvBack.text =
+                    getString(R.string.screen_message_detail_title_receive)
                 binding.tvKeep.visibility = View.VISIBLE
                 binding.tvReply.visibility = View.VISIBLE
                 binding.tvDelete.visibility = View.VISIBLE
             }
 
             messageBox == MessageBox.KEEP.name -> {
-                binding.toolbar.tvBack.text = "저장한 메시지 상세"
+                binding.toolbar.tvBack.text =
+                    getString(R.string.screen_message_detail_title_keep)
                 binding.tvKeep.visibility = View.GONE
                 binding.tvReply.visibility = View.GONE
                 binding.tvDelete.visibility = View.VISIBLE
             }
 
             else -> {
-                binding.toolbar.tvBack.text = "보낸 메시지 상세"
+                binding.toolbar.tvBack.text =
+                    getString(R.string.screen_message_detail_title_sent)
                 binding.tvKeep.visibility = View.GONE
                 binding.tvReply.visibility = View.GONE
                 binding.tvDelete.visibility = View.VISIBLE
@@ -86,7 +89,7 @@ class TextMessageDetailActivity : BaseActivity<ActivityTextMessageDetailBinding>
             if (messageItem!!.isKept) {
                 Toast.makeText(
                     applicationContext,
-                    "이미 보관된 메시지 입니다.",
+                    R.string.screen_message_detail_keep_already,
                     Toast.LENGTH_LONG
                 ).show()
                 return@setOnClickListener
@@ -98,7 +101,7 @@ class TextMessageDetailActivity : BaseActivity<ActivityTextMessageDetailBinding>
             viewModel.deleteMessage {
                 Toast.makeText(
                     applicationContext,
-                    "메시지가 삭제되었습니다.",
+                    R.string.screen_message_detail_delete_success,
                     Toast.LENGTH_LONG
                 ).show()
 
@@ -132,13 +135,23 @@ class TextMessageDetailActivity : BaseActivity<ActivityTextMessageDetailBinding>
         binding.tvMessage.text = messageItem?.textMessage
         binding.tvDate.text = messageItem?.date!!.convertDateFormat(
             from = "yyyy-MM-dd hh:mm:ss",
-            to = "yyyy년 MM월 dd일 E요일 HH:mm"
+            to = getString(R.string.screen_message_detail_date_format)
         )
     }
 
     private fun bindData() {
         viewModel.toastLiveData.observe(this) {
-            it?.let { Toast.makeText(applicationContext, it, Toast.LENGTH_LONG).show() }
+            it?.let { toast ->
+                val message = toast.message
+                val text = message ?: toast.resId?.let { resId -> getString(resId) }
+                text?.let { textMessage ->
+                    Toast.makeText(
+                        applicationContext,
+                        textMessage,
+                        Toast.LENGTH_LONG
+                    ).show()
+                }
+            }
         }
 
         viewModel.isLoading.observe(this) {
diff --git a/app/src/main/java/kr/co/vividnext/sodalive/message/text/TextMessageDetailViewModel.kt b/app/src/main/java/kr/co/vividnext/sodalive/message/text/TextMessageDetailViewModel.kt
index bc4243a8..bb52a29f 100644
--- a/app/src/main/java/kr/co/vividnext/sodalive/message/text/TextMessageDetailViewModel.kt
+++ b/app/src/main/java/kr/co/vividnext/sodalive/message/text/TextMessageDetailViewModel.kt
@@ -5,15 +5,17 @@ import androidx.lifecycle.MutableLiveData
 import com.orhanobut.logger.Logger
 import io.reactivex.rxjava3.android.schedulers.AndroidSchedulers
 import io.reactivex.rxjava3.schedulers.Schedulers
+import kr.co.vividnext.sodalive.R
 import kr.co.vividnext.sodalive.base.BaseViewModel
 import kr.co.vividnext.sodalive.common.SharedPreferenceManager
+import kr.co.vividnext.sodalive.common.ToastMessage
 import kr.co.vividnext.sodalive.message.MessageRepository
 
 class TextMessageDetailViewModel(private val repository: MessageRepository) : BaseViewModel() {
     var messageId: Long = 0
 
-    private val _toastLiveData = MutableLiveData<String?>()
-    val toastLiveData: LiveData<String?>
+    private val _toastLiveData = MutableLiveData<ToastMessage?>()
+    val toastLiveData: LiveData<ToastMessage?>
         get() = _toastLiveData
 
     private var _isLoading = MutableLiveData(false)
@@ -22,7 +24,7 @@ class TextMessageDetailViewModel(private val repository: MessageRepository) : Ba
 
     fun keepTextMessage() {
         if (messageId <= 0) {
-            _toastLiveData.postValue("알 수 없는 오류가 발생했습니다. 다시 시도해 주세요.")
+            _toastLiveData.postValue(ToastMessage(resId = R.string.common_error_unknown))
             return
         }
 
@@ -39,21 +41,23 @@ class TextMessageDetailViewModel(private val repository: MessageRepository) : Ba
                         _isLoading.value = false
                         if (it.success) {
                             _toastLiveData.postValue(
-                                "보관되었습니다."
+                                ToastMessage(resId = R.string.screen_message_detail_keep_success)
                             )
                         } else {
                             if (it.message != null) {
-                                _toastLiveData.postValue(it.message)
+                                _toastLiveData.postValue(ToastMessage(message = it.message))
                             } else {
                                 _toastLiveData.postValue(
-                                    "알 수 없는 오류가 발생했습니다. 다시 시도해 주세요."
+                                    ToastMessage(resId = R.string.common_error_unknown)
                                 )
                             }
                         }
                     },
                     {
                         it.message?.let { message -> Logger.e(message) }
-                        _toastLiveData.postValue("알 수 없는 오류가 발생했습니다. 다시 시도해 주세요.")
+                        _toastLiveData.postValue(
+                            ToastMessage(resId = R.string.common_error_unknown)
+                        )
                         _isLoading.value = false
                     }
                 )
@@ -62,7 +66,7 @@ class TextMessageDetailViewModel(private val repository: MessageRepository) : Ba
 
     fun deleteMessage(onSuccess: () -> Unit) {
         if (messageId <= 0) {
-            _toastLiveData.postValue("알 수 없는 오류가 발생했습니다. 다시 시도해 주세요.")
+            _toastLiveData.postValue(ToastMessage(resId = R.string.common_error_unknown))
             return
         }
 
@@ -81,17 +85,19 @@ class TextMessageDetailViewModel(private val repository: MessageRepository) : Ba
                             onSuccess()
                         } else {
                             if (it.message != null) {
-                                _toastLiveData.postValue(it.message)
+                                _toastLiveData.postValue(ToastMessage(message = it.message))
                             } else {
                                 _toastLiveData.postValue(
-                                    "알 수 없는 오류가 발생했습니다. 다시 시도해 주세요."
+                                    ToastMessage(resId = R.string.common_error_unknown)
                                 )
                             }
                         }
                     },
                     {
                         it.message?.let { message -> Logger.e(message) }
-                        _toastLiveData.postValue("알 수 없는 오류가 발생했습니다. 다시 시도해 주세요.")
+                        _toastLiveData.postValue(
+                            ToastMessage(resId = R.string.common_error_unknown)
+                        )
                         _isLoading.value = false
                     }
                 )
diff --git a/app/src/main/res/layout/activity_text_message_detail.xml b/app/src/main/res/layout/activity_text_message_detail.xml
index 51e36447..b859df70 100644
--- a/app/src/main/res/layout/activity_text_message_detail.xml
+++ b/app/src/main/res/layout/activity_text_message_detail.xml
@@ -93,7 +93,7 @@
             android:background="@drawable/bg_round_corner_6_7_3bb9f1"
             android:fontFamily="@font/gmarket_sans_bold"
             android:gravity="center"
-            android:text="답장"
+            android:text="@string/screen_message_detail_action_reply"
             android:textColor="@color/color_eeeeee"
             android:textSize="14.7sp" />
 
@@ -106,7 +106,7 @@
             android:background="@drawable/bg_round_corner_6_7_13181b"
             android:fontFamily="@font/gmarket_sans_bold"
             android:gravity="center"
-            android:text="보관"
+            android:text="@string/screen_message_detail_action_keep"
             android:textColor="@color/color_3bb9f1"
             android:textSize="14.7sp" />
 
@@ -118,7 +118,7 @@
             android:background="@drawable/bg_round_corner_6_7_13181b"
             android:fontFamily="@font/gmarket_sans_bold"
             android:gravity="center"
-            android:text="삭제"
+            android:text="@string/screen_message_detail_action_delete"
             android:textColor="@color/color_3bb9f1"
             android:textSize="14.7sp" />
     </LinearLayout>
diff --git a/app/src/main/res/values-en/strings.xml b/app/src/main/res/values-en/strings.xml
index 55b4af9d..f9514838 100644
--- a/app/src/main/res/values-en/strings.xml
+++ b/app/src/main/res/values-en/strings.xml
@@ -260,6 +260,16 @@
     <string name="screen_message_empty">No messages.\nTry connecting with friends!</string>
     <string name="screen_message_loading_text">Loading text messages…</string>
     <string name="screen_message_loading_voice">Loading voice messages…</string>
+    <string name="screen_message_detail_title_receive">Received message</string>
+    <string name="screen_message_detail_title_keep">Saved message</string>
+    <string name="screen_message_detail_title_sent">Sent message</string>
+    <string name="screen_message_detail_action_reply">Reply</string>
+    <string name="screen_message_detail_action_keep">Save</string>
+    <string name="screen_message_detail_action_delete">Delete</string>
+    <string name="screen_message_detail_keep_success">Saved.</string>
+    <string name="screen_message_detail_keep_already">Already saved.</string>
+    <string name="screen_message_detail_delete_success">Message deleted.</string>
+    <string name="screen_message_detail_date_format">MMM d, yyyy (EEE) HH:mm</string>
     <string name="screen_live_loading">Loading live rooms…</string>
     <string name="screen_live_cancel_title">Cancel reservation</string>
     <string name="screen_live_cancel_hint">Enter a reason for cancellation.</string>
diff --git a/app/src/main/res/values-ja/strings.xml b/app/src/main/res/values-ja/strings.xml
index db4f6d49..ee0b90f8 100644
--- a/app/src/main/res/values-ja/strings.xml
+++ b/app/src/main/res/values-ja/strings.xml
@@ -260,6 +260,16 @@
     <string name="screen_message_empty">メッセージがありません。\n友達と交流してみましょう！</string>
     <string name="screen_message_loading_text">テキストメッセージを読み込み中です。</string>
     <string name="screen_message_loading_voice">ボイスメッセージを読み込み中です。</string>
+    <string name="screen_message_detail_title_receive">受信メッセージ詳細</string>
+    <string name="screen_message_detail_title_keep">保存メッセージ詳細</string>
+    <string name="screen_message_detail_title_sent">送信メッセージ詳細</string>
+    <string name="screen_message_detail_action_reply">返信</string>
+    <string name="screen_message_detail_action_keep">保存</string>
+    <string name="screen_message_detail_action_delete">削除</string>
+    <string name="screen_message_detail_keep_success">保存しました。</string>
+    <string name="screen_message_detail_keep_already">既に保存されたメッセージです。</string>
+    <string name="screen_message_detail_delete_success">メッセージを削除しました。</string>
+    <string name="screen_message_detail_date_format">yyyy年 MM月 dd日 E曜日 HH:mm</string>
     <string name="screen_live_loading">ライブを読み込み中です。</string>
     <string name="screen_live_cancel_title">予約キャンセル</string>
     <string name="screen_live_cancel_hint">キャンセル理由を入力してください。</string>
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 2c670cdf..89a8d50f 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -259,6 +259,16 @@
     <string name="screen_message_empty">메시지가 없습니다.\n친구들과 소통해보세요!</string>
     <string name="screen_message_loading_text">문자 메시지를 불러오고 있습니다.</string>
     <string name="screen_message_loading_voice">음성 메시지를 불러오고 있습니다.</string>
+    <string name="screen_message_detail_title_receive">받은 메시지 상세</string>
+    <string name="screen_message_detail_title_keep">저장한 메시지 상세</string>
+    <string name="screen_message_detail_title_sent">보낸 메시지 상세</string>
+    <string name="screen_message_detail_action_reply">답장</string>
+    <string name="screen_message_detail_action_keep">보관</string>
+    <string name="screen_message_detail_action_delete">삭제</string>
+    <string name="screen_message_detail_keep_success">보관되었습니다.</string>
+    <string name="screen_message_detail_keep_already">이미 보관된 메시지 입니다.</string>
+    <string name="screen_message_detail_delete_success">메시지가 삭제되었습니다.</string>
+    <string name="screen_message_detail_date_format">yyyy년 MM월 dd일 E요일 HH:mm</string>
     <string name="screen_live_loading">라이브를 불러오고 있습니다.</string>
     <string name="screen_live_cancel_title">예약취소</string>
     <string name="screen_live_cancel_hint">취소사유를 입력하세요.</string>