diff --git a/src/core/arm/skyeye_common/vfp/vfpsingle.cpp b/src/core/arm/skyeye_common/vfp/vfpsingle.cpp
index f5410fd9a..6c33d8b78 100644
--- a/src/core/arm/skyeye_common/vfp/vfpsingle.cpp
+++ b/src/core/arm/skyeye_common/vfp/vfpsingle.cpp
@@ -614,7 +614,7 @@ static u32 vfp_single_ftoui(ARMul_State* state, int sd, int unused, s32 m, u32 f
         exceptions |= FPSCR_IDC;
 
     if (tm & VFP_NAN)
-        vsm.sign = 0;
+        vsm.sign = 1;
 
     if (vsm.exponent >= 127 + 32) {
         d = vsm.sign ? 0 : 0xffffffff;