A combined sensor and bearing assembly (1) is of a type having a capability of detecting a point of origin and includes a rolling bearing unit (6) and a rotation sensor unit (31). The rolling bearing unit (6) is made up of a rotatable raceway member (4), a stationary raceway member (5) and at least one row of rolling elements (3). The rotation sensor unit (31) includes a to-be-detected member (8) having a magnet and fitted to one of the raceway members (4, 5), and a magnetic detecting member (9) fitted to the other raceway member (4, 5) at a location confronting the to-be-detected member (8). This combined sensor and bearing assembly (1) is used at a location close to an electromagnetic coil (17) emanating a leakage magnetic field, in a condition in which a direction of flow of an electric current through the electromagnetic coil (17) is fixed in one direction so that a direction of a magnetic flux, with which the magnetic detecting member (9) is switched off, may coincide with a direction of the leakage magnetic flux.