In airtoair autonomous attackthe Unmanned Combat Aerial Vehicles (UCAV) has the disadvantages of small attack zonepoor mobilityand time lag of information link.To solve the problemsan approach of autonomous attack was proposed aimed to improve attack precision and combat effectiveness.Kinematic and dynamic models of UCAV and the guided missile were formed based on the characteristics of airtoair autonomous attack.The attack zone and noescape zone were calculated out by using the pattern search algorithmthrough which the optimum launch position was indicated.To arrive at the optimum launch positionsliding mode control was used to design the process of autonomous attacking occupationwhich was simulated later.The simulation result demonstrates that UCAV can arrive at the optimum launch position in a short time with stable gestureand attack the target effectively.