Objective: To analyze the efficiency of Tianjin 77 public hospitals’ medical service and it’s Influencing factors. Methods: Using DEA method to measure the hospitals’ medical service efficiency, establishing Tobit regression model to analyze the influencing factors of public hospitals medical service efficiency. Results: The overall efficiency of Tianjin public hospitals is low, most hospitals are not reasonable in the size, the significant influencing factors of Tianjin public hospitals’ medical service efficiency include the per capita physician outpatient, the proportion of senior technical staff, hospital gearing ratio, drug-income ratio and average fee per patient. Conclusion: Increasing the per capita physician outpatient, the proportion of senior technical staff can significantly enhance the overall technical efficiency, and decreasing the gearing ratio and the average fee of per patient is also beneficial to improve hospital efficiency.