The invention belongs to the technical field of bearings and aims to overcome the defects that the traditional machine tool bearing retainer has heavy weight and poor lubricating function. The invention provides a high-speed angular contact ball bearing of a light-weight retainer with dual grooves. The common structure of the retainer is changed into a dual-groove shape. The retainer is provided with an inside-diameter groove and a small outside-diameter groove of a pocket, wherein the inside-diameter groove can reduce the weight of the retainer, has small inertial force when the bearing rotates at a high speed and is suitable for high-speed rotation. The small outside-diameter groove is guided by an outer ring; grease is stored in the outside-diameter groove; and a lubricating oil film is formed at a guide surface for ensuring the rotary stability of the retainer under the high speed condition, thereby achieving the aims of low heating and low friction at a high speed and improvement on the precision, the service life and the stability of the bearing.