diff --git a/src/battle_util.c b/src/battle_util.c
index af620d2f9b..ebdc2063b9 100644
--- a/src/battle_util.c
+++ b/src/battle_util.c
@@ -1520,6 +1520,8 @@ u8 DoBattlerEndTurnEffects(void)
                 && ability != ABILITY_MAGIC_GUARD)
             {
                 gBattleMoveDamage = gBattleMons[gActiveBattler].maxHP / 8;
+                if (ability == ABILITY_HEATPROOF)
+                    gBattleMoveDamage /= 2;
                 if (gBattleMoveDamage == 0)
                     gBattleMoveDamage = 1;
                 BattleScriptExecute(BattleScript_BurnTurnDmg);