A mower deck lift mechanism for a lawn mower includes a mower deck, a linkage mechanism for movably mounting the mower deck to the frame for raising and lowering movement relative to the frame, and an electro-hydraulic actuator assembly connected to the linkage mechanism for raising and lowering the mower deck relative to the frame. The actuator assembly is an integrated unit including a hydraulic piston-cylinder assembly connected to the linkage mechanism, a pump for supplying pressurized fluid to the piston-cylinder assembly, and an electric motor for driving the pump.