Large-scale optical glasses are widely used and have special requirements. Analysis of large-scale optical glass machining showed that discrete particle machining was the key process. The conceptions, present research status, development tendency of a variety of discrete particle polishing methods were introduced and their machining accuracy, quality and efficiency were reviewed. The conceptions, equipments, status research of controllable slurry polishing were illustrated and study on it showed that it was a method worth paying attention to.