Aiming at the difficulty of recogniseing complex multi-pointer instruments, this paper presents an automatic recognition system of analog measuring instruments based on region growing. The whole algorithm consists of pointer extraction algorithm based on region growing method and pointer recognition algorithm based on hit-miss transform method or least square method. Besides, the seeds needed by region growing can automatically obtained by fuzzy clustering based on difference image. Experiments show that, the pointer extraction algorithm based on region growing method effectively extract the features of pointers. And the extraction algorithm lays the foundation for the Hit-Miss transform method and the least square method to obtain good recognition accuracy. The algorithm is fast and efficient, can satisfy the requirements of real-time applications. This paper first applies region growing method of image segmentation to the field of analog measuring instruments recognition, enriches the method of analog measuring instruments recognition, achieved good recognition effect.