The invention provides a processing method of a micro-miniature part with an open pore, which comprises the following steps: preparing, grinding, positioning, punching and deburring: in the preparation step, preparing a product to be punched; in the grinding step, a to-be-punched surface of the to-be-punched product is ground to form a grinding surface, and the light reflectivity of the grinding surface is smaller than that of the to-be-punched surface; in the positioning step, an optical image capturing device is adopted to position a position to be punched on a grinding surface; in the punching step, laser punching is conducted on the position to be punched, and a punched product is formed. In the deburring step, burrs on the periphery of the open hole are removed, and a deburring product is formed. According to the method, the grinding face with the light reflectivity smaller than that of the face to be punched is ground, so that the influence of reflected light on positioning is reduced, the punching error can be reduced through laser punching, meanwhile, burrs cannot appear on the hole wall of the punched hole, the burrs only appear on the back face, the deburring step is simplified, and operation is convenient.