In a portable electronic device having two circuit boards having a heat generating electronic device, a frame arranged at a position pinched between the circuit boards, a first heat radiating plate brought into contact with the frame and having a higher thermal conductivity than the frame, and a second heat radiating member transferring a heat between the first heat radiating member and two circuit boards, each of two circuit boards is fixed to the frame and two circuit boards are directly connected by a connector. Accordingly, it is possible to provide the portable electronic device which can improve a heat radiating efficiency and achieve a further thin structure.