A heat exchanger comprising: a heat exchange unit group made up of a plurality of heat exchange units arranged in a row direction, the row direction being a direction of air flow, the heat exchange units including a plurality of heat transfer tubes (13a-13d) configured to allow refrigerant to pass therethrough, the heat transfer tubes (13a-13d) being arrayed in a level direction, the level direction being perpendicular to the direction of air flow, and a plurality of fins (12a-12d) stacked to allow air to pass in the air flow direction; and headers (20, 30) disposed on both ends of the heat exchange unit group, the headers (20, 30) being connected with ends of the plurality of heat transfer tubes (13a-13d), the heat exchange unit group including one or more bend sections bent in the row direction, the headers (20, 30) including one header provided on one end of the heat exchange unit group in common for the plurality of rows of the heat exchange units, and a plurality of separate headers (20a-20d) provided separately for the heat exchange units on the other end of the heat exchange unit group, characterised in that the plurality of separate headers (20a-20d) being arranged at positions different between adjacent ones of the heat exchange units, the positions being different in a fin-stacking direction in which the plurality of fins (12a-12d) are stacked, wherein portions at respective ends, on which the separate headers (20a-20d) are provided, of the plurality of heat transfer tubes (13a-13d) project stepwise in the fin-stacking direction to position the plurality of separate headers (20a-20d) offset from each other, the portions of the plurality of heat transfer tubes (13a-13d) and the plurality of separate headers (20a-20d) more projecting in upstream than downstream of the air flowing between the plurality of fins (12a-12d), and the plurality of fins (12a-12d) are stacked across the heat transfer tubes (13a-13b) including the portions (14a-14d) projecting of the heat transfer tubes (13a-13d) between the one header and the separate headers (20a-20d). a heat exchange unit group made up of a plurality of heat exchange units arranged in a row direction, the row direction being a direction of air flow, the heat exchange units including a plurality of heat transfer tubes (13a-13d) configured to allow refrigerant to pass therethrough, the heat transfer tubes (13a-13d) being arrayed in a level direction, the level direction being perpendicular to the direction of air flow, and a plurality of fins (12a-12d) stacked to allow air to pass in the air flow direction; and a plurality of heat transfer tubes (13a-13d) configured to allow refrigerant to pass therethrough, the heat transfer tubes (13a-13d) being arrayed in a level direction, the level direction being perpendicular to the direction of air flow, and a plurality of fins (12a-12d) stacked to allow air to pass in the air flow direction; and headers (20, 30) disposed on both ends of the heat exchange unit group, the headers (20, 30) being connected with ends of the plurality of heat transfer tubes (13a-13d), the heat exchange unit group including one or more bend sections bent in the row direction, the headers (20, 30) including one header provided on one end of the heat exchange unit group in common for the plurality of rows of the heat exchange units, and a plurality of separate headers (20a-20d) provided separately for the heat exchange units on the other end of the heat exchange unit group, characterised in that the plurality of separate headers (20a-20d) being arranged at positions different between adjacent ones of the heat exchange units, the positions being different in a fin-stacking direction in which the plurality of fins (12a-12d) are stacked, one header provided on one end of the heat exchange unit group in common for the plurality of rows of the heat exchange units, and a plurality of separate headers (20a-20d) provided separately for the heat exchange units on the other end of the heat exchange unit group, characterised in that the plurality of separate headers (20a-20d) being arranged at positions different between adjacent ones of the heat exchange units, the positions being different in a fin-stacking direction in which the plurality of fins (12a-12d) are stacked, wherein portions at respective ends, on which the separate headers (20a-20d) are provided, of the plurality of heat transfer tubes (13a-13d) project stepwise in the fin-stacking direction to position the plurality of separate headers (20a-20d) offset from each other, the portions of the plurality of heat transfer tubes (13a-13d) and the plurality of separate headers (20a-20d) more projecting in upstream than downstream of the air flowing between the plurality of fins (12a-12d), and the plurality of fins (12a-12d) are stacked across the heat transfer tubes (13a-13b) including the portions (14a-14d) projecting of the heat transfer tubes (13a-13d) between the one header and the separate headers (20a-20d).