There are several different sources of thermal energy acting on a spacecraft as it flying on heat dreariness orbit;solar radiation,albedo,earth emitted infrared,and heat generated by camera equipment itself. Temperature fluctuating is a bad influence on imaging quality of high resolution camera. Purpose of thermal control is to maintain all the components of a spacebased camera within their respective temperature limits. Detailed thermal analysis and temperature calculation in different work status is put in practice on a spacebased high resolution camera as a whole in the paper,the result can supply references to thermal control for spacebased high resolution camera.