The invention discloses a vector displacement propelling device for a rotor wing and fixed wing combined vertical take-off and landing aircraft.The vector displacement propelling device comprises two propeller displacement devices and vector propelling devices.The two propeller displacement devices are symmetrically provided with gaps formed in the edges of left and right wings of the aircraft respectively for changing the propeller pitch, and then the thrust generated by the displacement propeller is precisely adjusted.The two propeller displacement devices are each provided with one vector propelling device for controlling the corresponding propeller displacement device to rotate up and down, the pitching angle of the displacement propeller is changed, and the thrust direction is changed.The vector displacement propelling device has the advantages that the effects of the vector adjusting devices and the propeller displacement devices are combined, the control torque of the pitching and roll-on and roll-off directions can be provided, and the overall flight posture can be precisely adjusted.