PROBLEM TO BE SOLVED: To provide a bearing with a magnetic fluid seal capable of attaining smooth rolling of a rolling body by reducing rotation torque.SOLUTION: A bearing 1 with a magnetic fluid seal includes a bearing body comprising: an inner ring 3 comprising a magnetic material; an outer ring 5 comprising a magnetic material; a rolling body 7 inserted in a rollable manner between the inner ring 3 and the outer ring 5. The bearing 1 also includes a magnetic fluid seal 10 held integrally with the bearing body and forming a magnetic circuit between the inner ring and outer ring to seal the inside of the bearing body. The magnetic fluid seal 10 comprises a magnet 12, a polar plate 14 holding the magnet, and a magnetic fluid. The rolling body 7 of the bearing body comprises a non-magnetic material.