A capacitor device has an accommodating case in which a plurality of accommodating parts are formed for accommodating capacitor main bodies. The plurality of accommodating parts are oriented so that the longitudinal directions thereof all face the same direction, and the plurality of capacitor main bodies are accommodated in the accommodating parts in a manner such that the sides having terminal parts are set up in the same orientation. The sides of the capacitor main bodies having the terminal parts are provided with engaging parts that engage with engaged parts provided to a predetermined element member, and the capacitor main bodies are accommodated all together in the accommodating case in a manner such that the engaging parts are engaged with the engaged parts.