A multi-input charging system and method use a motor driving device. The system includes: a motor having a plurality of windings; a first inverter including first switching elements and having one end connected to a power input terminal and an opposite end connected to a first terminal of each of the plurality of windings; a second inverter including second switching elements and having one end connected to a battery and an opposite end connected to a second terminal of each of the plurality of windings, the battery connected to the power input terminal or the one end of the second inverter; and a controller configured to charge the battery directly via the power input terminal or with a voltage of the charging power that is stepped down.