Abstract: To develop an intelligent lower limb rehabilitation instrument which could realize the quantification and visualization of lower limbs' raising angle and frequency, using the smart client to realize the remote control, autonomous data acquisition and the establishment of database. Doctors had the access to the database in order to adjust the rehabilitation program in time to meet the individual requirement. We realized the design of intelligent lower limb instrument based on the Andriod smartphone, which is suitable for clinical and family use.