The semiconductor device comprises a capacitor formed over a semiconductor substrate 10 and including a lower electrode 32, a dielectric film 34 formed over the lower electrode and an upper electrode 36 formed over the dielectric film, a first insulation film 42 formed over the semiconductor substrate and the capacitor, a first interconnection 48 formed over the first insulation film and electrically connected to the capacitor, a first hydrogen diffusion preventive film 50 for preventing the diffusion of hydrogen formed over the first insulation film, covering the first interconnection, a second insulation film 58 formed over the first hydrogen diffusion preventive film and having the surface planarized, a third insulation film 62 formed over the second insulation film, a second interconnection 70b formed over the third insulation film, and a second hydrogen diffusion preventive film 72 for preventing the diffusion of hydrogen formed on the third insulation film, covering the second interconnection. Since the second hydrogen diffusion preventive film positioned above the capacitor is planarized, the dielectric film is surely prevented from being reduced with hydrogen.