Abstract: Effects of the space environmental contamination on spacecraft is one of a very important issue for currently high reliability and high longevity.For observation satellites、astronomy satellites、monitoring and tracking satellites so on，cryogenic detectors，cryogenic optical systems and space cryogenerator are their major components.Therefor，the impact of the space environment and contamination on space cryogenerator would endanger the reliability of spacecraft.Very thin deposited films of contamination gases can significantly influence the emissivity of low emittance surface.Due to an increase in emittance make cryogenic heat load increase of space mechanical cryogenerator 10%～20%，also lead to elevate radiant cryogenerator temperature and cause failure of the cooled device.Paper describes some of specific contamination control methods and the physics controlling contamination sensitivity，discuss a number of contamination-related physical phenomena.Contamination methods of cryogenerator is that cryogenerator are carefully isolated from sources of external contamination using multilayer insulation or physical barriers.Control contamination of radiant cryogenerator must be start from the ground.During the installation，assembly，testing and integration process with spacecraft should be carried out in a clean environment.Its way to control contamination is correct structural design and must be required to minimize the susceptibility of the radiant cryogenerator to contamination.