diff --git a/server/gameserver/boxdrop.cc b/server/gameserver/boxdrop.cc
index a941e23a..e3a1b308 100644
--- a/server/gameserver/boxdrop.cc
+++ b/server/gameserver/boxdrop.cc
@@ -71,11 +71,11 @@ void BoxDrop::OnHumanDeadDrop(Human* hum)
     for (int i = 0; i < hum->box_num; ++i) {
         int rnd = a8::RandEx(0, 100);
         if (hum->stats->abandon_battle) {
-            if (rnd <= mt::Param::s().battle_event_end_loss_rate_quit * 100) {
+            if (rnd <= (mt::Param::s().battle_event_end_loss_rate_quit * 100)) {
                 ++drop_num;
             }
         } else {
-            if (rnd <= mt::Param::s().battle_event_end_loss_rate_dead * 100) {
+            if (rnd <= (mt::Param::s().battle_event_end_loss_rate_dead * 100)) {
                 ++drop_num;
             }
         }