Abstract: Aim To analyze generation mechanisms of acoustic emission in grinding pro- cess , gives acoustic emission signal mathematical model , and use the new type fluid AE senser to monitor the grinding process. Methods Transmission characteristics of dif- ferent type of acoustic emission signal of grinding process through fluid acoustic emis- sion sensor were discussed, and the influence of some factors such as angle and veloci- ty of fluid ejection on its transmission characteristics were analyzed theoretically. Re- sults Experiments showed its applicability and gave acoustic emission signal characteristics. Conclusion A new way to monitor grinding process by a new type flu- id AE sensor is revealed.