diff --git a/src/mmg/mmg.cpp b/src/mmg/mmg.cpp
index 55659eeab..734d6ed2a 100644
--- a/src/mmg/mmg.cpp
+++ b/src/mmg/mmg.cpp
@@ -1226,6 +1226,8 @@ mmg_dialog::update_command_line() {
 
   clargs.Clear();
   clargs.Add(mkvmerge_path);
+  clargs.Add(wxT("--output-charset"));
+  clargs.Add(wxT("UTF-8"));
   clargs.Add(wxT("-o"));
   clargs.Add(tc_output->GetValue());
   args_start = clargs.Count();
diff --git a/src/mmg/tab_input.cpp b/src/mmg/tab_input.cpp
index 1ab013736..b45b2c8d0 100644
--- a/src/mmg/tab_input.cpp
+++ b/src/mmg/tab_input.cpp
@@ -761,7 +761,7 @@ tab_input::add_file(const wxString &file_name,
                  wxICON_ERROR);
     throw 0;
   }
-  opt_file->Write(wxT("--identify-verbose\n"));
+  opt_file->Write(wxT("--output-charset\nUTF-8\n--identify-verbose\n"));
   arg_utf8 = to_utf8(file_name);
   opt_file->Write(arg_utf8.c_str(), arg_utf8.length());
   opt_file->Write(wxT("\n"));