To provide a high accuracy for circular rotation of a motor shaft and a pump shaft so that a joint non-rotatably interconnecting both shafts is formed with the requirement for a slight accuracy.

In this pump unit 10 having an electric motor 12 and a radial piston pump 14, a motor shaft 32 and a pump shaft 20 are supported by one common bearing 30 in order to save bearings. In order to compensate for alignment errors, the pump shaft 20 is non-rotatably connected to the motor shaft 32 via a joint shaft 44. In that case, the joint shaft 44 is non-rotatably brought into form engagement with the motor shaft 32 and the pump shaft 20 via a multi-edge contour 48, with a play of angles and an axial play.