Low temperature stop valve is applicable to the management system of cryogenic liquid storage and transportation equipment, with the characteristics of flexible switch and reliable sealing, and can also be used for other cryogenic and cryogenic medium management systems. Low temperature stop valve usually refers to the stop valve with operating temperature lower than -110℃, which is widely used in liquefied natural gas, liquefied petroleum gas and other low-temperature industries. At present, low temperature stop valves applicable to temperatures up to -196℃ can be manufactured. All parts are subject to low temperature pretreatment with liquid nitrogen to completely avoid seal deformation and leakage during use.