diff --git a/engine/battle/move_effects/thief.asm b/engine/battle/move_effects/thief.asm
index bc31ca390..9f2a2cc8d 100644
--- a/engine/battle/move_effects/thief.asm
+++ b/engine/battle/move_effects/thief.asm
@@ -71,6 +71,11 @@ BattleCommand_Thief:
 	farcall ItemIsMail
 	ret c
 
+; Wildmons can't steal items
+	ld a, [wBattleMode]
+	dec a
+	jr z, .cant
+
 	ld a, [wEffectFailed]
 	and a
 	ret nz
@@ -108,3 +113,7 @@ BattleCommand_Thief:
 	ld e, l
 	ld hl, wEnemyMonItem
 	ret
+
+.cant
+	or 1
+	ret