In the environment of strong electromagnetic countermeasure, many kinds of radio navigation systems may be interfered. The corresponding navigation sensors can’t obtain the complete measurement information of the system and carry out independent positioning, which leads to the problem that the navigation system can’t effectively locate. In this paper, a method of multi-source information fusion is proposed. This method uses the incomplete measurement information of multiple navigation system, corrects the time difference and pseudo range inconsistency of, realizes the unification of the measurement information in time and space, and then uses the least square method for multi-source pseudo range joint location. Finally, the effectiveness of the method is verified by the laboratory simulation experiment, which improves the location availability and reliability of multi-source integrated navigation equipment.