Abstract: A major challenge affecting the performance of Wireless sensor networks (WSNs) comes from the unbalanced traffic over different parts of networks. High delay in transmitting information from one node to another is the prime reason behind unbalanced energy consumption .delay has continuous nature; even if two nodes are placed in bounded area, there is an infinite number of possible values for delay between them. A natural solution to reduce the delay is to have the data collector that will collect the information from all the nodes but in large network single data collector would not work efficiently; so we propose solution to this problem is to have multiple mobile data collectors so that the load is distributed evenly among all nodes. We investigate this promising direction for balancing the load and, hence, minimized the delay in the network. We divide the network into multiple clusters and placed a mobile data collector in each cluster. We show, by theoretical analysis and simulations, that our approach has the potential to prolong the lifetime of the network significantly by minimizing the delay as comparisons to other schemes.