A heat exchanger includes a heat exchange core, an introduction tank for introducing a heat transfer medium into the heat exchange core, and a discharge tank for receiving the heat transfer medium discharged from the heat exchange core. Materials used to form the introduction tank and the discharge tank are different from each other. The properties desired for the respective tanks may be attained, and while unnecessary increases in the costs for manufacturing the heat exchanger is may be reduced or avoided, the performance of the heat exchanger may be improved.