Rotator cuff injury is a common shoulder pathology and its prevalence increases with age.Surgery can greatly improve the clinical symptoms of patients compared to conservative treatment.However,postoperative complications such as postoperative pain and postoperative retear are controversial.In recent years,a new treatment option,hydrogel,has received much attention.Although most researches on hydrogels are still in the experimental stage,their therapeutic promise remains highly anticipated.This article provides an overview of the classification of hydrogels applied to the rotator cuff and the researches on various hydrogels with different active ingredients in rotator cuff injuries.Future applications of hydrogels are expected as well.