The present invention provides a heat exchanger which comprises a pair of headers and a plurality of flat tubes (11a to 11f), and which makes it possible to achieve both improvement in the pressure strength of the headers and control of the pressure loss of a refrigerant. The headers comprise: a first member (131); and a flat tube holding member (132) which holds the flat tubes (11a to 11f) due to the end parts of the flat tubes (11a to 11f) being adhered thereto. The first member (131) comprises: a main refrigerant passage (131a) which extends in the vertical direction and has a refrigerant flowing therethrough; and linking refrigerant passages (231a to 231f) which lead from the main refrigerant passage (131a) to an end face in the direction in which the flat tubes (11a to 11f) are disposed in order to circulate refrigerant between the main refrigerant passage (131a) and a plurality of refrigerant passages formed in the flat tubes (11a to 11f). Intermediate passages (133a to 133f) which connect the linking refrigerant passages (231a to 231f) and the plurality of refrigerant passages of the flat tubes (11a to 11f) are formed in the headers and/or the flat tubes (11a to 11f).
