The present invention relates to communication technologies, and provides a method, system and device for grouping a mobile Instant Messaging (IM) contact. The system includes a positioning module, configured to query information of a region at which a mobile terminal of a mobile IM contact locates; and an automatic grouping module, configured to obtain the information of the region at which the mobile terminal of the mobile IM contact locates from the positioning module, and group the mobile IM contact according to the information of the region. Embodiments of the present invention may improve the accuracy of the grouping result, and may greatly improve the efficiency of the grouping.