A semiconductor device and a method of manufacturing the same with easy formation of a phase change film is realized, realizing high integration at the time of using a phase change film as a memory element.Between MISFET of the region which forms one memory cell, and MISFET which adjoined it, each source of MISFET adjoins in the front surface of a semiconductor substrate, insulating. And the multi-layer structure of a phase change film, and the electric conduction film of specific resistance lower than the specific resistance is formed in the plan view of the front surface of a semiconductor substrate ranging over each source of both MISFET, and a plug and a plug stacked on it. The multi-layer structure functions as a wiring extending and existing in parallel on the surface of a semiconductor substrate, and an electric conduction film sends the current of a parallel direction on the surface of a semiconductor substrate.