A battery operated handheld power tool, comprising a working tool assembly (20), a handle assembly (10) and an elongate tubular rod (30). The working tool assembly (20) comprises a motor housing (26) having a first inner space (27), comprising an electric motor (21) with a fan (25). The first inner space (27) is connected to the exterior of the working tool assembly (20) by means of at least one air outlet (28). The handle assembly (10) comprises a second inner space (19) in which a control unit (15) is positioned, the second inner space (19) being in flow communication with the exterior of the handle assembly (10). The elongate tubular rod (30) defines an air guiding channel (33), in flow communication with the first inner space (27) and the second inner space (19).