diff --git a/logic/service/fight/input/prop.go b/logic/service/fight/input/prop.go
index 2c6989340..26f645c35 100644
--- a/logic/service/fight/input/prop.go
+++ b/logic/service/fight/input/prop.go
@@ -33,7 +33,7 @@ func (target *Input) SetProp(source *Input, index, level int8) bool {
 	switch {
 	case level < 0:
 		if target.AttackValue.Prop[index] > -6 {
-			target.AttackValue.Prop[index] -= level
+			target.AttackValue.Prop[index] += level
 		} else {
 			return false
 		}