The invention relates to a motor/pump unit, especially for antislip automotive brake systems, comprising a receiving body (3) for hydraulically active components, an internal geared wheel pump with pump components comprising a pinion internal geared wheel combination disposed between two housing parts (20,21), said pump components forming a pre-mounted unit, and a motor (2) for driving the internal geared wheel pump. The aim of the invention is to provide a motor/pump unit which enables the internal geared wheel pump to be integrated into a receiving body in a space-saving and low-cost manner. This is achieved by arranging the housing parts (20,21) in a temporarily adjacent manner by means of at least one security element (38, 46) such that a final orientation of the housing parts (20,21) in relation to each other occurs when the unit is inserted into the receiving body (3).