A mechanical and hydraulic double action releasing tool is used for the completion drilling operation of the oil and gas field. A body cavity of an external cylinder assembly is provided with an annular flute, which is matched with a claw sleeve of a feeding tool. A lower sliding sleeve is in sliding clearance fit with a lower contact. A hydraulic chamber is formed by a lower sliding sleeve cavity step and the lower contact. A plurality of radial through holes is arranged on a center rod, in communication with the hydraulic chamber. An upper sliding sleeve and middle sliding sleeve are secured together by a shear pin. The external surface of the upper sliding sleeve is equipped with a step, which is matched with the cavity step of the claw sleeve. The middle sliding sleeve is fastened on the center rod by the shear pin. An anti-rotation mechanism is positioned between the external cylinder assembly and the feeding tool assembly. The releasing operation in mechanical or hydraulic mode can be realized by the utility model through the structural improvement of the tool, so as to solve the problem that the releasing cannot be carried out in regular reverse mode due to the disallowance of the rotation of the completion pipe string and the other special reasons, and the opposite rotation of the blocking piece and the body can be prevented by the special matching structure.