Abstract: This paper discusses some subjects about the orbit keeping of the sun-synchronous repeating orbit by the analytical point of view. The factors that affect the action of the sun-synchronous repeating orbit are put forward,which include non-sphere perturbation, air-drag and sun-gravity resonance. These analysis lay the foundation for the research of orbit keeping of the sun-synchronous repeating orbit. The result of quantitative analysis shows that the method is feasible, and be helpful for the research of orbit design and control.