The invention discloses a plug pin pressing and positioning device based on sliding fixation and hydraulic pressure balance. The structure of the device comprises a fixing shell, a sliding self-locking devices, sliding slots, a right horizontal plate, an anti-torsion sleeve, a groove, a left horizontal plate, a hydraulic pressure balance movable pin device and a power source line. The sliding self-locking device is adopted; a lower suction cup and a rubber pad are matched with each other so as to initially fix a corresponding positioning adsorption structure; a pressing clamping buckle and a spur gear are matched with each other, so that the self-locking position of the positioning adsorption structure can be adjusted; and the positioning adsorption structure is unlikely to slide. The hydraulic pressure balance movable pin device is adopted; a pressurization structure and a sliding fastening structure are matched with each other, so that a special-shaped fixing column has two connection states, namely, a clearance fit state and an interference fit state; in the insertion and removal process of pins, the special-shaped fixing column is in interference fit with the sliding fasteningstructure; and during the energization process of the pins, the special-shaped fixing column is in clearance fit with the sliding fastening structure.