The temperature variety of the outer baffle for space camera directly affects the temperatures of optical components around the baffle. The thermal deformation of optical components would decrease the quality of image. Three different thermal control approaches were stated out for the baffle of a high-resolution space camera and the analysis and comparison among them were accomplished. Firstly, the most common thermal control means of baffle for space camera were introduced. The orbit heat flux and heat resistant between the baffle and the main body of camera, which affect the temperature of the baffle, were calculated and discussed. Then temperatures and powers of active heaters in three cases were obtained via simulation analysis. After comparison, the third design approach was adopted because of the low power of active heater and high temperature stability. Finally, the thermal design was validated in the thermal balance test and temperature test in orbit. The temperature range of the baffle is between 4.8 ℃ to 13.6 ℃ and the second mirror is between 17.8 ℃ to 17.9 ℃. The data in orbit are consistent with the analysis results, which indicate that the thermal design is valid and reasonable which can meet the mission requirements.