Obtaining the angles between the moving target and the radar is very important in the study of radar cross section(RCS) of moving targets. The angles between the moving target and the radar were defined and calculated in detail. The differences and relationship of angles from static targets and moving targets were also discussed. The method of quasi-static was used to analyze the scattering from moving target. In high frequency approximate, RCS comes from the contributions of face scatter, edge scatter and corner reflector, ect. Because of the influence of airflow, the aircraft will be tremored in random. A kind of tremor model was used to analyze the effect of tremor on RCS. It indicates that the deviate degree of RCS increases with the frequency, the effect from tremor on RCS is different at different angles,and it is tremendous in certain angles.