In order to improve the cooling of an electrical machine, the invention proposes an electrical machine having a stator (4) and a rotor, wherein the stator (4) has a cooling jacket (10) over at least part of the stator (4), wherein the cooling jacket (10) has a motor jacket (3) surrounding the stator (4) and an outer jacket (1), at least sections of which are spaced apart from said motor jacket (3), and a hollow helix (2) is arranged in the section between the motor jacket (3) and the outer jacket (1) and has a predeterminable pitch (12), and wherein the inlet (7) and the outlet (6) of this cooling jacket (10) are located substantially on an axial plane of the electrical machine.