An endoscope apparatus comprising: a solid-state imaging element including a light receiving surface on a front face thereof; a circuit board arranged on a rear face side of the solid-state imaging element; a laminated circuit board formed on an upper surface of the circuit board and having a plurality of conductor layers, the laminated circuit board including a wiring pattern a part of which is exposed on a distal end side of the circuit board, a distal end side of the laminated circuit board facing the solid-state imaging element; a first heat dissipation member arranged between the solid-state imaging element and the exposed part of the wiring pattern, the first heat dissipation member being in contact with the rear face of the solid-state imaging element and the exposed part of the wiring pattern; a cable (33a, 33b) electrically connected to the wiring pattern; a cable connection land disposed on a proximal end side of a lower surface of the circuit board for connection with the cable; a board connection land disposed on the upper face of the circuit board for connection with the laminated circuit board, wherein the circuit board comprises an opening formed on a resist layer on the circuit board to expose a wiring pattern having contact with the first heat dissipation member; wherein a width of the exposed part of the wiring pattern in contact with the first heat dissipation member is wider than a width of the wiring pattern at a central part of the laminated circuit board; wherein the board connection land and the cable connection land are electrically connected to each other through the wiring pattern, and wherein the circuit board and the laminated circuit board are adhered with each other with an adhesive in the board connection land. a solid-state imaging element including a light receiving surface on a front face thereof; a circuit board arranged on a rear face side of the solid-state imaging element; a laminated circuit board formed on an upper surface of the circuit board and having a plurality of conductor layers, the laminated circuit board including a wiring pattern a part of which is exposed on a distal end side of the circuit board, a distal end side of the laminated circuit board facing the solid-state imaging element; a first heat dissipation member arranged between the solid-state imaging element and the exposed part of the wiring pattern, the first heat dissipation member being in contact with the rear face of the solid-state imaging element and the exposed part of the wiring pattern; a cable (33a, 33b) electrically connected to the wiring pattern; a cable connection land disposed on a proximal end side of a lower surface of the circuit board for connection with the cable; a board connection land disposed on the upper face of the circuit board for connection with the laminated circuit board, wherein the circuit board comprises an opening formed on a resist layer on the circuit board to expose a wiring pattern having contact with the first heat dissipation member; wherein a width of the exposed part of the wiring pattern in contact with the first heat dissipation member is wider than a width of the wiring pattern at a central part of the laminated circuit board; wherein the board connection land and the cable connection land are electrically connected to each other through the wiring pattern, and wherein the circuit board and the laminated circuit board are adhered with each other with an adhesive in the board connection land.