Objective: To study validity and reliability of Wolf motor function test (WMFT) on assessing the upper extremities motor function of acute stroke patients so as to guide clinical application. Method: Twenty-three stroke patients in acute stage participated in the study. Patients were assessed twice with WMFT and the upper extremities motor function test of Fugl-Meyer movement assessment (U-FMA) within one week. The correlation between the assessment results of WMFT and U-FMA were analyzed to study the validity and reliability of WMFT. Result: WMFT was highly correlated with U-FMA in total scores (r =0.922, 0.929, P＜0.001). There were high correlation in all items of WMFT between two assessment sessions. The intraclass correlation coefficients (ICC) were 0.989, 0.997 for intrarater and 0.980, 0.991 for interrater. Conclusion: The WMFT is valid and reliable on assessing upper extremities motor function of stroke patients in acute stage.