On a surface of an anode member 12 having a valve action, a cathode layer 14 is formed, and at a terminal lead-out face 12a at one end of the anode member 12, an anode wire 16 is led out of it; thus a capacitor element 10 is formed. An anode terminal 4 is joined to the anode wire 16. A cathode terminal 5 is joined to the cathode layer 14. A protective layer 2 of resin covers part or all of the capacitor element 10. A packaging member 3 of resin harder than the protective layer 2 covers around the capacitor element 10 including the protective layer 2 and the anode wire 16 to form a package. The protective layer 2 has a larger linear expansion coefficient than the packaging member 3. The mass ratio of the packaging member 3 to the total mass of the packaging member 3 and the protective layer 2 between the terminal lead-out face 12a and the exterior face of the packaging member 3 opposite the terminal lead-out face 12a is 50% or more.