The invention discloses a high-precision curve transmission measuring system, which comprises a transmission unit, a vacuum sealing unit, a moving control unit and a measuring unit, wherein the transmission unit comprises a guide rail, a slide block, trolleys, a transmission rod, an electric cylinder and a support mechanism; a plurality of trolleys are put on the guide rail; a sensor is arranged on the front end of the first trolley; the vacuum sealing unit comprises an insertion plate valve, a vacuum cavity and a vacuum sealing mechanism; the transmission rod and the guide rail penetrate through the vacuum sealing unit and are connected with the trolleys and the electric cylinder; the moving control unit comprises a servo motor, a speed reducer, a motor driver, a grating ruler, a real-time controller and a position limiting switch; the controller drives the servo motor through the motor driver; the electric cylinder is driven to move through the speed reducer; the grating ruler participates in the position feedback; the position limiting switch makes protection; the measuring unit comprises a sensor and corresponding signal collection processing equipment. The curve transmission is used in the vacuum environment; the high-precision movement and measurement inside the vacuum and in other limited space can be realized.