A construction machine comprising: an undercarriage; an upperstructure that is turnably provided on the undercarriage and has a turning frame including a center frame and side frames provided on the right and the left of the center frame; an engine room that is provided on the upperstructure; a reducing agent tank that is disposed in a radiator space adjacent to the engine room, and stores a reducing agent; an engine, a cooling fan that rotates by driving of the engine, an injector that injects the reducing agent to exhaust gas exhausted from the engine, and a reducing agent hose that connects the injector and the reducing agent tank, which are provided in the engine room; and a heat exchanger that is disposed between the reducing agent tank and the cooling fan, performs heat exchange by cooling air generated by rotation of the cooling fan to cool the engine, characterized in that the construction machine further comprises a bracket for placing the heat exchanger, the bracket being mounted on a side frame of the turning frame and being composed of a strength member having a cross-section substantially of a downwardly opened U-shape, the strength member having a first side plate section facing a side of the radiator space on which the reducing agent tank is disposed, a second side plate section facing an inside of the engine room, and a top plate section connecting the first side plate section and the second side plate section, wherein a first cutout section for allowing the reducing agent hose to be inserted, and a second cutout section for allowing the reducing agent hose to be inserted are provided in the first side plate section and the second side plate section respectively, and a portion of the reducing agent hose is disposed to pass through the first cutout section, through an internal space of the bracket and through the second cutout section. an undercarriage; an upperstructure that is turnably provided on the undercarriage and has a turning frame including a center frame and side frames provided on the right and the left of the center frame; an engine room that is provided on the upperstructure; a reducing agent tank that is disposed in a radiator space adjacent to the engine room, and stores a reducing agent; an engine, a cooling fan that rotates by driving of the engine, an injector that injects the reducing agent to exhaust gas exhausted from the engine, and a reducing agent hose that connects the injector and the reducing agent tank, which are provided in the engine room; and a heat exchanger that is disposed between the reducing agent tank and the cooling fan, performs heat exchange by cooling air generated by rotation of the cooling fan to cool the engine, characterized in that the construction machine further comprises a bracket for placing the heat exchanger, the bracket being mounted on a side frame of the turning frame and being composed of a strength member having a cross-section substantially of a downwardly opened U-shape, the strength member having a first side plate section facing a side of the radiator space on which the reducing agent tank is disposed, a second side plate section facing an inside of the engine room, and a top plate section connecting the first side plate section and the second side plate section, wherein a first cutout section for allowing the reducing agent hose to be inserted, and a second cutout section for allowing the reducing agent hose to be inserted are provided in the first side plate section and the second side plate section respectively, and a portion of the reducing agent hose is disposed to pass through the first cutout section, through an internal space of the bracket and through the second cutout section.