Automatic bus charging prompt device

The utility model provides an automatic bus charging prompt device. The automatic bus charging prompt device comprises a bus punch-card machine, a photosensitive sensor at a coin insertion port, an infrared inductor, a PLC controller and an acousto-optic prompting device. The PLC controller carries out logic determination according to a punch-card signal of the bus punch-card machine, a coin insertion signal of the photosensitive sensor at the coin insertion port and a human body identification signal transmitted by the infrared inductor to output a charging-or-not signal to the acousto-optic prompting device, and the acousto-optic prompting device receives the charging-or-not signal to determine whether sound or light are emitted to prompt timely payment. The automatic bus charging prompt device can detect whether each passenger on a bus has paid for travel and further prompts the passenger for payment.