A bearing assembly for a transmission, which is capable of avoiding an ingress of foreign matter, reducing seal torque and reducing shear resistance between a retainer and balls, includes a recessed portion in an inner face of a pocket of the retainer, in which the surface area of contact with a ball is smaller than the surface area of contact when no recessed portion is provided. A sealing member is a contact seal and material of a tip portion of a sealing lip region is highly wearable material which, when the bearing assembly is rotated, wears to define a non-contact or the like. A grease contains a base oil and a thickening agent and the base oil is a mineral oil alone or a mixed oil of mineral oil and poly-α-olefin oil and has base oil kinetic viscosity not higher than 100 mm2/s at 40° C.