Composite PCB (printed circuit board) multilayer circuit board

The utility model discloses a composite PCB multilayer circuit board, and relates to the technical field of circuit boards. Comprising a shell, a sealing cover is fixedly installed on the front side face of the shell through a locking mechanism, an installation frame is arranged between the shell and the front inner wall and the rear inner wall of the sealing cover, springs are fixedly installed on the side faces of the periphery of the installation frame, and a circuit board body is fixedly installed in the installation frame through first locking bolts. Contact pins are arranged on the front side face and the rear side face of the circuit board body and fixedly embedded in the rear side wall of the shell and the sealing cover, heat dissipation mechanisms are arranged at the positions, close to the front portion and the rear portion, between the left inner wall and the right inner wall of the shell, and three sets of heat dissipation mechanisms are arranged front and back. The buffering and damping functions