The utility model discloses a scaling piston is pressed to variable lift based on wireless WIFI, including wireless WIFI module (20), wireless WIFI module (21), controller (22), driver (23), step motor (12, 14) and piston (13), the instruction of wireless WIFI module (21) received, the work of control driver (23) drive step motor are read in the instruction that regulating press scaling was sent with wireless mode to wireless WIFI module (21) through wireless module (20) in car ECU (19), controller (22), when car ECU (19) sends the instruction of increase engine compression ratio, step motor corotation, the lift of piston increases to the pressure scaling of increase engine sends when reducing the engine and pressing the scaling instruction as car ECU (19), the step motor reversal, and the piston lift reduces, thereby reduces the pressure scaling of engine, when the engine need not change pressure scaling, car ECU (19) not give -out order, step motor is out of work, and the pressure scaling of engine is unchangeable.