diff --git a/src/CRE/pv_param.cpp b/src/CRE/pv_param.cpp
index 6e511be5..2c9c9fcf 100644
--- a/src/CRE/pv_param.cpp
+++ b/src/CRE/pv_param.cpp
@@ -407,9 +407,13 @@ namespace pv_param {
 
     void light_data_struct::clear_data() {
         chara_light_file.clear();
+        chara_light_file.shrink_to_fit();
         stage_light_file.clear();
+        stage_light_file.shrink_to_fit();
         chara_light.clear();
+        chara_light.shrink_to_fit();
         stage_light.clear();
+        stage_light.shrink_to_fit();
     }
 
     bool light_data_struct::load_file(std::string& file, std::map<int32_t, light_param_light_data>& map) {