Abstract: In order to meet the navigation demand of the Mars exploration cruise phase, an autonomous navigation method based on observing the Sun, Mars, Earth and Stars with different sensors is presented in this paper. According to the characteristics of celestial navigation, the paper analyzes the different observation models. After that, according to the operability of the Line-of-Sight between Earth and Mars, two navigation models are established which use the Sun, Earth and Star observations and the Sun, Mars, Star observations, respectively. Then combined with information fusion technology, a real-time position and velocity estimation of the probe is achieved in any kind of navigation model. Finally, the feasibility of the method is verified by simulations. Simulation results show that the proposed method can be more feasible and efficient using multi-source observations, and can provide precise orbit determination information which meets the navigation requirements of the Mars exploration cruise phase.