To provide a washing machine which prevents the damage of an electronic device being left forgotten in clothing by notifying a user that the electronic device is sensed in a water tank before supplying water.

The washing machine 10 is equipped with a metal detector 16 which is provided on the throw-in port of the water tank 11 and detects a metal in the water tank 11. The metal detector 16 has a transmitting coil along the outer periphery of the water tank 11 and first and second receiving coils which are respectively provided along the outer periphery of the water tank 11 with spacing on both sides of the transmitting coil. Electric current is conducted through the transmitting coil and the metal is detected by the change of the electromotive force of the first and second receiving coils when a specimen passes. When the metal is detected, a loudspeaker 14 makes an alarm sound and an alarm lamp 13a emits an alarm light.