To clean an ink supply passage substantially entirely such that ink is not left after cleaning.

A subtank 10 mounted on a head carriage 6 is coupled with one main carrying passage. The other side of the main carrying passage is branched into an ink supply section including a pump 30, first and second solenoid valves 48 and 50 before and behind the pump, and a third solenoid valve 52 being coupled with one solenoid valve 48 out of the solenoid valves 48 and 50, an ink collecting section sharing the first and second solenoid valves 48 and 50 with the pump 30, and a cleaning liquid supply section sharing the first, second and third solenoid valves 48, 50 and 52 with the pump 30. Ink supply, ink collection and cleaning liquid supply are carried out, respectively, through the pump 30 by switching the solenoid valves.