Aiming at the problem of multi-missile cooperative attack on enemy air targets, a multi-missile and multi-constraint three-dimensional cooperative guidance method based on sliding mode control theory and artificial potential field method is deduced. Firstly, according to the relative motion of the missile and the target, a three-dimensional non-linear model of the relative motion between the missile and the target was established in the line-of-sight coordinate system. Then, taking the remaining flight time of multiple bombs as the coordination variable, based on the finite time consistency theory, the guidance law of the direction of sight of multiple bombs is designed, which realizes the coordinated attack on the target. On this basis, the normal direction of sight guidance law of multi-missile is designed through the sliding mode control theory, so that the multi-projectile can hit the enemy target at a given line of sight angle, and according to the convergence characteristics of the sliding mode surface, the parameters are adaptively updated to reduce the sliding mode parameter selection complexity. In addition, considering the difficulty in obtaining target maneuver information, an expanded state observer is designed to efficiently predict target acceleration information. Finally, combined with the idea of artificial potential field method, a multi-missile obstacle avoidance control command is designed to effectively avoid constraints such as avoidance zones during multi-missile flight. The simulation results verify the effectiveness of the proposed guidance method.