A head unit includes a common passage, at least one recording head, and a joint mechanism. The joint mechanism has a first valve and couples the common passage to the recording head. The first valve includes: a first stopper having a switch member with an insertion hole and an engagement boss projecting from its inner surface, a sliding portion inserted in the insertion hole slidably up and down, and an engagement groove engaged with the engagement boss; and a first sealing member fitted on the first stopper to be in contact with or away from the insertion hole's inner surface. Rotating the switch member to move the first stopper up/down causes the first valve to switch between a closed state, with the first sealing member in contact with the insertion hole's inner surface, and an open state, with the first sealing member away from the insertion hole's inner surface.