The present invention addresses the problem of providing a charging device capable of precisely outputting charging power to a battery or the like within a broad voltage range of tens-to-hundreds of volts. This charging device comprises: a converter unit that outputs a charging voltage to a battery and a control unit that outputs a control signal of a pulse width determined on the basis of the voltage value of the charging voltage to a switching element of the converter unit, thereby setting the switching element to a conducting state for only a time corresponding to the pulse width. The control unit changes the output interval for the control signal in accordance with the output interval for the control signal as the voltage value of the charging voltage decreases.