diff --git a/modules/arena/api_challenge.go b/modules/arena/api_challenge.go
index 10fb27c5e..cfdc6018a 100644
--- a/modules/arena/api_challenge.go
+++ b/modules/arena/api_challenge.go
@@ -141,6 +141,7 @@ func (this *apiComp) Challenge(session comm.IUserSession, req *pb.ArenaChallenge
 		Integral: red.Integral,
 		Dan:      red.Dan,
 	}
+
 	this.module.modelArena.integralCompute(redplay, &pb.ArenaPlayer{
 		Uinfo:    bule.Uinfo,
 		Integral: bule.Integral,
diff --git a/modules/arena/modelarena.go b/modules/arena/modelarena.go
index bce910625..eb4220d88 100644
--- a/modules/arena/modelarena.go
+++ b/modules/arena/modelarena.go
@@ -410,14 +410,23 @@ func (this *modelArena) integralCompute(red, bule *pb.ArenaPlayer, iswin bool) {
 	if iswin {
 		red.Changeintegral = int32(float64(redactive.KValue) * float64(1-1/float32(1+math.Pow(10, float64(float64(bule.Integral-red.Integral)/400)))))
 		bule.Changeintegral = int32(float64(buleactive.KValue) * float64(0-1/float64(1+math.Pow(10, float64(float64(red.Integral-bule.Integral))/400))))
-		red.Integral = red.Integral + red.Changeintegral
-		bule.Integral = bule.Integral + bule.Changeintegral
 	} else {
 		red.Changeintegral = int32(float64(redactive.KValue) * float64(0-1/float64(1+math.Pow(10, float64(float64(bule.Integral-red.Integral)/400)))))
 		bule.Changeintegral = int32(float64(redactive.KValue) * float64(1-1/float64(1+math.Pow(10, float64(float64(red.Integral-bule.Integral)/400)))))
+	}
+	if red.Integral+red.Changeintegral < 0 {
+		red.Changeintegral = -red.Integral
+		red.Integral = 0
+	} else {
 		red.Integral = red.Integral + red.Changeintegral
+	}
+	if bule.Integral+bule.Changeintegral < 0 {
+		bule.Changeintegral = -bule.Integral
+		bule.Integral = 0
+	} else {
 		bule.Integral = bule.Integral + bule.Changeintegral
 	}
+
 }
 
 func (this *modelArena) recoverTicket(session comm.IUserSession, info *pb.DBArenaUser) {