Abstract: To solve the problem of the passive tracking of the space objects with perturbation in space-based optical surveillance, the hybrid coordinates SPKF method is put forward. The Unscented Transformation (UT) and hybrid coordinates are introduced to avoid the influence of the linearization error and enhance the robustness of the tracking filter. The state prediction is performed in Cartesian coordinates utilizing UT and the perturbation influence could be considered at the same time, then the filter updating procedure is performed in modified sphere coordinates. Simulation results indicate that this approach has more advantage on rapidity of convergence and stability under the condition of the dense or sparse measurements.