A heat exchanger unit includes: a first heat exchanger including a first header, a second header, and a first flat pipe group that includes first flat multi-hole pipes connected to each of the first header and the second header; and a second heat exchanger: disposed in parallel with the first heat exchanger on an air downstream side, from the first heat exchanger, of air flow generated by a fan; and including a third header, a fourth header, and a second flat pipe group that includes second flat multi-hole pipes connected to each of the third header and the fourth header. The fourth header causes a refrigerant that flows in from the third header to flow out to the first header.