Aiming at the problems of existing unmanned platforms in path planning such as taking up many resources and easily falling into local minima, this paper was introduced the Homotopy algorithm to carry out the research of path planning method for unmanned platforms. By applying the Homotopy Continuation Method (HCM) to construct a constrained nonlinear path equation with simple graphs instead of complex obstacles, and solving the equation by using the homotopy property of the attraction tendency of the target point and the repulsion tendency of the obstacles, and finally conducting simulation experiments, the results show that the method can generate collision-free paths, which provides a simple and feasible method for unmanned platform path planning.