A heat exchanger includes a core. The core includes a heat-exchange tube for a heat exchange medium to circulate therein. The core includes a fin joined to the heat-exchange tube. The heat exchanger includes a pair of header pipes connected with both ends of the core. Each of header pipes includes header pipe members. Each of header pipes has a joint member communicating with header pipe members. The joint member has communication holes arranged longitudinally of the header pipes at intervals.