The invention provides a human body motion state recognition method and system based on an acceleration sensor, which is divided into an offline stage and an online stage; wherein, the offline stage adopts the K-Means clustering method to construct a human body motion state recognition model, based on the existing tagged The data is used for training and research, and a classification strategy is proposed; then in the online stage, a real-time system for human motion state recognition is designed based on Android mobile phones, and the design is carried out from five functions: data collection, data processing, motion recognition, model update, and data display; finally, it is proved by experiments The effectiveness of the clustering algorithm, the experimental results show that it is feasible to build a human motion recognition model based on the clustering method, and the model has the advantages of good real-time performance, light weight and easy adjustment.