A stacking-type header includes: a first plate-shaped unit and a second plate-shaped unit having a distribution flow passage that includes a branching flow passage including: an opening port; a first straight-line part parallel to a gravity direction and having a lower end communicating with the opening port through a first connecting part; and a second straight-line part parallel to the gravity direction and having an upper end communicating with the opening port through a second connecting part, in which at least a part of the first and second connecting parts are not parallel to the gravity direction, and in which the refrigerant flows into the branching flow passage through the opening port, and flows out from the branching flow passage through each of an upper end of the first straight-line part-and a lower end of the second straight-line part.