Abstract: In this paper wavelet packet technique is used to decompose the vibration signals of grinding process.Since these decomposed signals in every band have different energy,they can be used to represent the vibration exception with fuzzy ART neural network.The fuzzy ART neural network can generate a new clustering to give an alarm when vibration exception of unknown pattern appears.Compared with traditional methods this method can identify the known and unknown pattern exceptions of grinding process.The result of practical application shows that this method is very efficient.