Abstract: Objective To investigate the changes of lower-extremity function and peroneal nerve function at different recovery phase in patients with post-stroke hemiplegia. Methods A total of 74 post-stroke hemiplegia patients were selected in our hospital from October,2015 to September,2016.The conventional medical treatment and rehabilitation training were performed in all patients.The lower-extremity function of patients was assessed with the Fugl-Meyer Assessment scaly after 1,3 and 6 months.The peroneal nerve function of patients was assessed by using common peroneal nerves conduction velocity.The difference in the functions after 1,3 and 6 months were compared.The correlation between lower-extremity function and common peroneal nerves conduction velocity was observed. Results Among the three recovery phases,Lower-extremity function had significant difference(F=53.950,P<0.001);peroneal nerve function of affected side had significant difference(F=3.241,P=0.045);peroneal nerve function of uninjured side had no significant difference(F=1.017,P=0.432).After 1 month and 3 months recovery,12 cases were with Grade 1 velopharyngeal function,14 cases with grade 2,and 3 cases with grade 3.The peroneal nerve function of affected side was significantly lower than that of uninjured side(t=-2.751,P=0.007;t=-2.540,P=0.012);After 6 months recovery,there was no significant difference between affected side and uninjured side(t=-1.371,P=0.173).FMA-L score increased with the extension of recovery time,there was a positive correlation(r=0.181,P=0.007);As the extension of recovery time,the common peroneal nerves conduction velocity accelerated,there was a positive correlation (r=0.181,P=0.007).There was a positive correlation between FMA-L score and common peroneal nerves conduction velocity(r=0.148,P=0.028). Conclusion As the extension of recovery time,lower-extremity function and peroneal nerve function can be gradually improved.The lower-extremity function is closely related to peroneal nerve function in patients with post-stroke hemiplegia.The combining monitoring on the lower-extremity function and peroneal nerve function will be helpful to the evaluation of prognosis of patients.