The invention relates to a system and a method of discovering a social group having unspecified behavior senses in a multi-dimensional space, and belongs to the data mining and knowledge discovery field. Whether users having similar behavior relation can be discovered according to similarity of tweet publishing geographic positions and similarity of unspecified behavior senses expressed by the tweet entries based on user social network twitter behavior tracks. According to the experiment, the accuracy of the method provided by the invention of discovering the groups having the similar behaviors is better than the conventional determination method, and therefore the high actual application value can be provided. When the system and the method provided by the invention can be popularized to the greatest extent, the industry innovation can be facilitated, the trans-boundary integration can be prompted, and the great benefits to the social livelihood can be provided, and then the national economic and social innovative development can be prompted.