The utility model discloses a high vacuum insulation cryotron heat leakage's measuring device, including the auxiliary test section of bisymmetry and gather gas flow's gas flow meter, heat leakage through measuring two secondary segments respectively and two secondary segments are the whole heat leakage of developmental tube in addition, thereby then calculates the heat leakage that both differences of value methods obtained being surveyed the high vacuum insulation cryotron. The utility model discloses can effectively overcome measure among the prior art heat leakage operation degree of difficulty big, measure inaccurately or calculate unsafe problem to make the heat leakage that testing personnel can the accurate high vacuum insulation of recording cryotron, provide the guarantee for thehigh vacuum insulation cryotron can move safely at the in -service use in -process effectively.