Velocity analysis includes searching for similarity values for velocities and times that are in a desired interval. In the usual method, a common midpoint operator is used for velocity analysis. The model-based common diffraction surface stack operator, which is an extension of the joint midpoint operator, is used to estimate the velocity. First, a velocity model of subsurface layers in Seismic Unix opensource software; It is built under the Linux operating system. Then, the seismic data of the relevant model was taken with a special arrangement. Finally, the results of analysis of velocity and discharge obtained from the two methods show well that in the proposed method, relying on special processing technique and focusing more on the diffraction emitters, there is the ability to determine the exact location of the reflector and the value of its velocity. has it. This is while in the usual method, it isn,t possible to determine the location of the reflector and its velocity well.