An automatic flush toilet includes a toilet stool with a toilet bowl, a water tank unit, a first discharge member, a second discharge member, a pipe unit, a flush valve, a manual actuating unit, an electric switching valve, and a sensor control unit. The electric switching valve is controlled by the sensor control unit to permit water discharged from the first discharge member to flush the toilet bowl. The flush valve is controlled by the manual actuating unit to permit water discharged from the second discharge member to flush the toilet bowl.