To provide an ink supply device for an ink jet printer in which maintenance work can be facilitated as compared with the conventional one.

An ink rack 3 is equipped with an ink tank 500 installed in a housing 400 and having a tank 510 for storing ink and a lid 520 which can be attached removably to the tank 510, an ink supply pipe 550 fixed, at one end thereof, to the lid 520 and inserted into the tank 510, a liquid level sensor 560, and wire members 414a and 414b which can hold the lid 520 separated from the tank 510 near the installation position in the housing 400. The tank 510 is configured so as to move downward from the installation position in the housing 400 in a state where the lid 520 is held by the wire members 414a and 414b.