Considering the geomagnetic field, the relativistic effect and bremsstrahlung radiation of high-energy protons, a single particle motion model of proton transport in the space environment is established. Based on this model, the Bayesian optimization method is proposed to realize the precise control of protons transport from the initial position to the target under a given proton energy. The dependence of the proton launch angle on the launch height is obtained, that is, when the coordinate radial angle is 0° and 180°, the value of the coordinate axial angle will not change the optimal emission direction of the particles. The results can provide theoretical references for long-distance transport of proton beams in the space environment.