An electric generator includes an electric-power generating mechanism of an electrostatic induction type or an electromagnetic induction type, a first rectification portion, an electricity accumulation portion, an outer positive electrode, and an outer negative electrode. The electric-power generation mechanism has a first electrode and a second electrode, and the first rectification portion has input terminals electrically connected to the first electrode and the second electrode respectively, and has an output portion including positive and negative terminals. The electricity accumulation portion has an inner positive electrode electrically connected to the positive terminal, and an inner negative electrode electrically connected to the negative terminal. The outer positive electrode is electrically connected to the inner positive electrode, and the outer negative electrode is electrically connected to the inner negative electrode. The electric generator has an outer shape which can be substituted for a battery to be used in the electronic apparatus.