Abstract: The cryogenic heat pipe is an efficient heat transfer device.It is used for space cryogenic heat transfer technology.An artery wick cryogenic heat pipe with nitrogen as the working fluid developed for spaceborne radiant coolers is described.It is fabricated of stainless steel tube with the diameter of 6mm and the length of 210mm,the operating temperature from 80K to 120K,the maximum heat transfer load reached 2.5W.An experimental investigation is described concerning the heat pipe heat transport characteristics. The results indicate that the heat conduction performance of the cryogenic heat pipe has the advantages of solid conductors at the same volume.It can meet entirely the demands of the low temperature focal plane coupling of the spaceborne radiant coolers.