As photographing and video parsing techniques improved, it provides a boost for taekwondo technical researching. This paper make analysis of every stage features of back kick skills by using video parsing data, then based on analysis human gravity shifting features and relative features between hip angle and kick velocity in motion process, through analysis of each link of lower limbs’ velocity status in five time phrases, get every links of lower limbs’ velocity feature in 4 stages. With the analysis data of taekwondo back kick motions time consuming in 4 stages, get the order of time consuming proportion from biggest to smallest like : the 4th stage> the 1st stage>the 2nd stage>the 3rd stage; it provides theoretical basis to sports analyzing and data references to taekwondo training.