In order to improve maneuver trajectory or design intercept guidance law effectively, qualitative analysis on pursuit and evasion should be launched including the relationship of normal overload, line-of-sight (LOS) angular speed variation trend, and intercept trajectory stability.Based on the simplified engage model, analytic formulas of the LOS angle velocity and the need normal acceleration of the pursuing missile were presented.Considering guidance system time delay, the steady conditions of the proportional navigation trajectory were obtained.The simulation on the lateral sinusoidal maneuver was performed, which proved rationality of the analytic formulas.