To provide a bearing unit for wheel support capable of rapidly and accurately replenishing a drop pocket with a rolling element when the rolling element drops from C and D set, and capable of reducing initial failure caused by erroneous assembly of the rolling element.

The bearing unit for wheel support is provided with a static ring 2 fixed to a vehicle body constituting member, a rotating ring 4 to which a wheel constituting member is fixed so as to be rotated with the wheel constituting member (a hub 10 and an inner ring constituting body 12), a plurality of rolling elements 20i and 20o incorporated between double row raceway surfaces 6i, 8i, 6o and 8o formed thereon and mutually opposed so as to be rolled, and annular holders 22i and 22o rotatably holding the rolling elements. The holder is equipped with a plurality of the pockets along the peripheral direction, and is incorporated between the raceway surfaces in the state that the rolling elements are inserted in the pockets and are rotatably held, and is provided with an identification means capable of being identified from the outside in accordance with a diameter dimension for each of the diameter dimensions of the rolling elements inserted into the pockets to be held.