To downsize a semiconductor device that includes a non-volatile memory and a capacitive element on a semiconductor substrate. In a capacitive element region of a main surface of a semiconductor substrate, fins protruding from the main surface are arranged along the Y direction while extending in the X direction. In the capacitive element region of the main surface of the semiconductor substrate, capacitor electrodes of the capacitive elements are alternately arranged along the X direction while intersecting the fins. The fins are formed in a formation step of other fins which are arranged in a memory cell array of the non-volatile memory of the semiconductor substrate. One capacitor electrode is formed in a formation step of a control gate electrode of the non-volatile memory. Another capacitor electrode is formed in a formation step of a memory gate electrode of the non-volatile memory.