The invention provides a fixed-wing unmanned plane formation guidance device and a collaborative tracking guidance method, and belongs to the technical field of unmanned plane flight control. On the basis of designing an embedded computer device for unmanned plane formation guidance, a collaborative tracking and ground target guidance method is designed. Firstly, a guidance method for a Leader unmanned plane to automatically track a ground target is designed. Secondly, a tracking guidance method for a Follower unmanned plane to automatically track the Leader unmanned plane, and a collaborative guidance method for the formation phase control are designed, and the stability analysis is carried out. Finally, the simulation verification is carried out for the tracking problem of a stationary target, a constant-speed linear motion target and a variable-speed motion target. According to the invention, the automatic collaborative tracking of various ground targets can be realized. Meanwhile, under the same condition, the tracking performance of the above method is obviously superior to that of a guidance method based on the classic Lyapunov vector quantity method.