diff --git a/example/cpp/windows/simple_tts/simple_tts.cpp b/example/cpp/windows/simple_tts/simple_tts.cpp
index 90b17c111..439ea9a8d 100644
--- a/example/cpp/windows/simple_tts/simple_tts.cpp
+++ b/example/cpp/windows/simple_tts/simple_tts.cpp
@@ -53,7 +53,8 @@ int main() {
       continue;
     }
     VoicevoxVoiceModel* model;
-    result = voicevox_voice_model_new_from_path(path.c_str(), &model);
+    result = voicevox_voice_model_new_from_path(wide_to_utf8_cppapi(path).c_str(),
+                                                &model);
     if (result != VoicevoxResultCode::VOICEVOX_RESULT_OK) {
       OutErrorMessage(result);
       return 0;
@@ -158,6 +159,8 @@ void OutErrorMessage(VoicevoxResultCode messageCode) {
   std::wcout << wideStr << std::endl;
 }
 
+// FIXME: codecvtはC++17から非推奨となり、win32で頑張って手書きしなければならない。それができたらvcxprojの_SILENCE_CXX17_CODECVT_HEADER_DEPRECATION_WARNINGを削除する。
+
 /// <summary>
 /// ワイド文字列をUTF8に変換します。
 /// </summary>
diff --git a/example/cpp/windows/simple_tts/simple_tts.vcxproj b/example/cpp/windows/simple_tts/simple_tts.vcxproj
index 988a5ee52..e091b6596 100644
--- a/example/cpp/windows/simple_tts/simple_tts.vcxproj
+++ b/example/cpp/windows/simple_tts/simple_tts.vcxproj
@@ -95,7 +95,7 @@
       <LanguageStandard>stdcpp17</LanguageStandard>
       <WarningLevel>Level3</WarningLevel>
       <SDLCheck>true</SDLCheck>
-      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;_SILENCE_CXX17_CODECVT_HEADER_DEPRECATION_WARNING;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <ConformanceMode>true</ConformanceMode>
       <AdditionalIncludeDirectories>..\..\..\core\src;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
     </ClCompile>
@@ -113,7 +113,7 @@
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <SDLCheck>true</SDLCheck>
-      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;_SILENCE_CXX17_CODECVT_HEADER_DEPRECATION_WARNING;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <ConformanceMode>true</ConformanceMode>
       <AdditionalIncludeDirectories>..\..\..\core\src;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
     </ClCompile>
@@ -131,7 +131,7 @@
       <LanguageStandard>stdcpp17</LanguageStandard>
       <WarningLevel>Level3</WarningLevel>
       <SDLCheck>true</SDLCheck>
-      <PreprocessorDefinitions>_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>_DEBUG;_CONSOLE;_SILENCE_CXX17_CODECVT_HEADER_DEPRECATION_WARNING;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <ConformanceMode>true</ConformanceMode>
       <AdditionalIncludeDirectories>..\..\..\core\src;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
     </ClCompile>
@@ -149,7 +149,7 @@
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <SDLCheck>true</SDLCheck>
-      <PreprocessorDefinitions>NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>NDEBUG;_CONSOLE;_SILENCE_CXX17_CODECVT_HEADER_DEPRECATION_WARNING;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <ConformanceMode>true</ConformanceMode>
       <AdditionalIncludeDirectories>..\..\..\core\src;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
     </ClCompile>