A capacitor comprising a capacitor element including a substrate having first and second faces, a porous first rough surface layer formed on the first face and having pores, a first inner conductive polymer layer formed in the pores, a first outer conductive polymer layer formed on the inner conductive polymer layer, a porous second rough surface layer formed on the second face and having pores, a second inner conductive polymer layer formed in the pores, a second outer conductive polymer layer formed on the second inner conductive polymer layer, and a dielectric layer formed on surfaces of the first and the second rough surface layer. A surface area of the second rough surface layer is smaller than that of the first rough surface layer. The second outer conductive polymer layer is thicker than the first outer conductive polymer layer. This structure enables to eliminate warpage of a capacitor element.