Using the velocities of P wave and S wave obtained from P wave and S wave VSP logging and based on the velocity model constructed from the least squares error, the authors have established the velocity parameters of P wave, S wave and converted wave in Jiyang area. With the converted wave velocity parameter, the interpretation precision of multiple wave data in Yanjia area has been raised. The velocity relationship between the P wave and the S wave deduced from various data provides basic data for the performance of mutiple wave exploration in this region.