Abstract: The anti-radiation property of one kind of PFPE grease used in spacecraft is studied.The condition of radiation test is 1.5×10⁴ rad（Si）.Structural analysis were carried out using infrared absorption spectrum.The results show that PFPE grease’s characteristic-C-O-C-chain hasn,t broken off.Only a few-C-C-chain broke off which resulted in some increase of grease’s outgas.The four-ball wear scar,four-ball extreme-pressure weld point,oil separation and vacuum evaporating rate in properties of greases which no and enduring radiation were evaluated.The results show that the above properties of radiating greases are consistent with those of no radiation ones.So PFPE grease can stand 1.5×10⁴ rad（Si） radiation condition.