To provide a retainer for a ball bearing of a double clasp type, having a structure with improved holding rigidity for balls, which is hard to be deformed by a centrifugal force during high speed rotation, and to appropriately suppress torque loss by smoothing a flow of lubricating oil for inside of pockets and thus reducing stirring resistance of the lubricating oil.

The retainer is equipped with first and second annular portions 21, 22 and a plurality of columns 26 coupling the first and second annular portions 21, 22 and separating and forming the plurality of pockets 25 for storing the balls 18. The retainer is separately composed of first and second divided bodies 30, 35 which are divided in the axial direction by the plurality of columns 26 and coupled at these column divided portions. A discharge groove 40 of the lubricating oil is provided in a recessed form in a part corresponding to the columns 26 which is at an outer diameter side of the first and second annular portions 21, 22. At the outer diameter part of the column 26, an introducing recessed part 50 for introducing the lubricating oil flowed out from the pocket 25 to the discharge groove 40 is provided in a recessed form.