diff --git a/pycm/pycm_obj.py b/pycm/pycm_obj.py
index <HASH>..<HASH> 100644
--- a/pycm/pycm_obj.py
+++ b/pycm/pycm_obj.py
@@ -400,7 +400,7 @@ class ConfusionMatrix():
                 matrix = self.table
                 if normalize:
                     matrix = self.normalized_table
-                csv_matrix_file = open(name + "_matrix" + ".csv", "w")
+                csv_matrix_file = open(name + "_matrix" + ".csv", "w", encoding="utf-8")
                 csv_matrix_data = csv_matrix_print(
                     self.classes, matrix, header=header)
                 csv_matrix_file.write(csv_matrix_data)
fix : minor bugs fixed. (encoding utf-8 added)