The research status of grinding process acoustic emission monitoring technology is systematically described from four aspects： grinding process acoustic emission monitoring principle， feature extraction and selection， monitoring model and monitoring system development. Firstly， a review of the sources and characteristics of acoustic emission signals in grinding is presented， focusing on the principles of acoustic emission monitoring in different grinding conditions. Then the common feature extraction and selection methods and monitoring models for acoustic emission monitoring of grinding processes are compared， and the advantages and disadvantages of each method are compared. The development of existing monitoring systems is summarized. Finally， the problems in the current research on acoustic emission monitoring of grinding processes are summarized and the future development direction is prospected.