The invention discloses a crossed block connection device capable of eliminating radial additional loads of a coupler. The end faces of adjacent teeth of a crossed block (4) of the device are provided with two through holes which are perpendicular to each other but are not communicated, wherein the axes of the two through holes pass through the center of the crossed block (4). The positive side faces and the negative side faces of opposite teeth of the crossed block (4) are respectively provided with two short holes perpendicular to the axes of the through holes, and a hinge pin I (2), a hinge pin II (7), a hinge pin III (9) and a hinge pin IV (12) are arranged in the short holes in a clearance fit mode, the two through holes are packed with liquid plastics (5, 11), and a screw I (3), a screw II (8), a screw III (10) and a screw IV (13) are used for tightly screwing and sealing four ports of the two through holes. When the crossed block connection device is transmitted, all parts are stressed constantly and synchronously, axial additional loads on a shaft due to unbalanced stress of the coupler are eliminated, the whole structure only transmits torque, and therefore the adverse effect of deformation of the connection shaft or vibration of a connection part or the like is avoided and the connection reliability of mechanical equipment is ensured.