Wireless sensor network (WSN) consists of a number of sensors, which measure and gather data in a variety of environments. In a WSN, sensed data are collected at a centralized location, called sink, for processing and analysis. With limited transmission ranges, sensed data may require multiple relays to reach the sink. In this thesis, a novel system design for multi-level clustering (MLC) WSNs and its associated protocol operations are proposed.Cluster-heads in the proposed design form a tree with a goal to reach all sensor nodes in the network. Subsequently, all sensed data in the tree are delivered to the sink. Energy savings is improved by exploiting sensor node redundancy in the WSN. To validate the proposed design, thorough simulations have been carried out. Upon comparing to the LEACH protocol, it offers consistent wider coverage area and longer life span of a WSN with proper settings of system parameters.