Abstract. Wireless sensor network is a suitable technology for ubiquitous environment. However, in WSN, as the network size grows larger, overheads such as flooding, calculation and memory overhead rapidly increase as well. For reducing the overhead of Micro Controller Unit (MCU) calculation and energy consumption, partitioning of WSN in several groups and hierarchy is suggested. For group formation, these mechanisms typically utilize predesigned network group information or location aware algorithms. However, the existing methods which use network topology information have node distribution and scalability problem in dynamic networks. Also, methods which use location-awareness have energy consumption problems. Therefore, we suggest a logical group formation and management mechanism using sensor association information and received signal strength indication without using any additional devices. With the help of proposed mechanism, WSNs would have stability and long lifetime.