Heat exchanger

Disclosed in the present invention is a heat exchanger. The heat exchanger comprises: an inlet header pipe, which is used for a heat exchange medium to flow into the heat exchanger, and comprises a first inlet header pipe portion and a second inlet header pipe portion; and heat exchange medium inlet pipes, which are respectively arranged at mutually adjacent ends of the first inlet header pipe portion and the second inlet header pipe portion and are respectively in fluid communication with the first inlet header pipe portion and the second inlet header pipe portion, wherein each heat exchange medium inlet pipe has an inlet. Since the heat exchange medium enters the inlet header pipe from the middle of the inlet header pipe, the optimization of distribution of the heat exchange medium is facilitated, and the heat exchange efficiency is increased.