A stacking-type header connected to a plurality of tubes including a first tube and a second tube and configured to allow inflow of fluid from the first tube and inflow of the fluid into the second tube , comprising: a first plate-like body having a plurality of first opening ports , each of the plurality of tubes being connected to a corresponding one of the plurality of first opening ports of the first plate-like body ; a plurality of second plate-like bodies (11b to 11d, 12b to 12d) having a plurality of second opening ports , the plurality of second plate-like bodies (11b to 11d, 12b to 12d) being stacked on the first plate-like body so that the plurality of second opening ports communicate with the plurality of first opening ports to form flow passages ; and one or more third plate-like bodies stacked on the plurality of second plate-like bodies (11b to 11d, 12b to 12d), wherein each of the flow passages has a flow passage area that continuously or gradually changes in a stacking direction of the plurality of second plate-like bodies (11b to 11d, 12b to 12d), the flow passages are provided to correspond to the plurality of tubes connected to the first plate-like body , each of the third plate-like bodies are provided with a connecting flow passage that allows communication between a flow passage corresponding to the the first tube and a flow passage corresponding to the second tube , characterized in that a central axis of each of the plurality of first opening ports and a central axis of each of the plurality of second opening ports of one of the plurality of second plate-like bodies that is located farthest away from the first plate-like body are eccentric to each other, and a central axis of each of the plurality of second opening ports in the flow passage corresponding to the first tube is eccentric toward the second tube with respect to a central axis of each of the plurality of first opening ports in the flow passage corresponding to the first tube . a first plate-like body having a plurality of first opening ports , each of the plurality of tubes being connected to a corresponding one of the plurality of first opening ports of the first plate-like body ; a plurality of second plate-like bodies (11b to 11d, 12b to 12d) having a plurality of second opening ports , the plurality of second plate-like bodies (11b to 11d, 12b to 12d) being stacked on the first plate-like body so that the plurality of second opening ports communicate with the plurality of first opening ports to form flow passages ; and one or more third plate-like bodies stacked on the plurality of second plate-like bodies (11b to 11d, 12b to 12d), wherein each of the flow passages has a flow passage area that continuously or gradually changes in a stacking direction of the plurality of second plate-like bodies (11b to 11d, 12b to 12d), the flow passages are provided to correspond to the plurality of tubes connected to the first plate-like body , each of the third plate-like bodies are provided with a connecting flow passage that allows communication between a flow passage corresponding to the the first tube and a flow passage corresponding to the second tube , characterized in that a central axis of each of the plurality of first opening ports and a central axis of each of the plurality of second opening ports of one of the plurality of second plate-like bodies that is located farthest away from the first plate-like body are eccentric to each other, and a central axis of each of the plurality of second opening ports in the flow passage corresponding to the first tube is eccentric toward the second tube with respect to a central axis of each of the plurality of first opening ports in the flow passage corresponding to the first tube . <EOS>