According to the present disclosure, a washing machine may comprise a cabinet, a tub disposed in the cabinet to receive water, a drum rotatably disposed in the tub to contain a laundry and a detergent supply device disposed at the cabinet to supply detergent into the tub, wherein the detergent supply device comprises a plurality of cartridges containing detergent, a pump suctioning detergent from the plurality of cartridges, a passage guiding detergent discharged from the pump into the tub and a plurality of electrode sensors disposed at a side of the plurality of cartridges, wherein each of the plurality of electrode sensors comprises an electrode plate detecting electric signal and a terminal transmitting the electric signal detected by the electrode plate, wherein the electrode plate has a first surface contacted with detergent contained in the cartridge and a second surface connected to the terminal.