The invention discloses a rotor wing with great lifting force. The rotor wing with great lifting force comprises a rotor wing rotation shaft and at least two paddles, wherein each paddle comprises an upper surface and a lower surface with aerodynamics; the front part of each paddle forms a front edge; the rear part of each paddle forms a rear edge; a groove is formed in the upper surface of each paddle; a cross flow fan is arranged in each groove; each cross flow fan comprises a cross flow fan rotation shaft and a plurality of cross flow fan blades which are evenly distributed at the periphery of the cross flow fan rotation shaft and are capable of rotating around the cross flow fan shaft; the cross flow fan rotation shaft protrudes out of end plates on two sides of each paddle; a transmission device is connected to the cross flow fan. Due to the adoption of the structure, the cross flow fans rotate, vortex lifting force can be generated; flow fields of the paddles are changed to generate great lifting force; driving force for rotating the rotor wing rotation shafts can be provided; the rotor wing becomes a self-driven rotor wing, so that the rotor wing is not required to be equipped with a torque resisting device, a large-weight speed reducer, a transmission device, a complex operation device and the like in the flight; a helicopter with the rotor wing is high in a ratio of the payload to the empty helicopter weight, great in power load and high in economic efficiency.