The present invention provides a vacuum thermal insulating valve that may be used at high temperature in gas supply systems or gas exhaust systems, and also may be made substantially small and compact in size owing to its excellent thermal insulating performance. With a vacuum thermal insulating valve comprising a valve equipped with a valve body and an actuator, and a vacuum thermal insulating box that houses the valve, the afore-mentioned vacuum thermal insulating box S is formed by a square-shaped lower vacuum jacket S5 having a cylinder-shaped vacuum thermal insulating pipe receiving part J on a side and with its upper face made open, and the square-shaped upper vacuum jackets S4, which is hermetically fitted to the lower vacuum jacket S5 and with its lower face made open.