Data aggregation is essential that exploits correlated sensing data and aggregates at intermediate nodes to reduce the number of messages and to improve the energy efficiency in wireless sensor networks. This project considers the problem of constructing data aggregation tree in a wireless sensor network for a group of source nodes to send sensory data to a single sink node. We propose an ant colony algorithm for data aggregation in wireless sensor networks. Simulation results have shown that our algorithm can reduce significant energy costs.-Data aggregation is essential that exploits correlated sensing data and aggregates at intermediate nodes to reduce the number of messages and to improve the energy efficiency in wireless sensor networks. This project considers the problem of constructing data aggregation tree in a wireless sensor network for a group of source nodes to send sensory data to a single sink node. We propose an ant colony algorithm for data aggregation in wireless sensor networks. Simulation results have shown that our algorithm can reduce significant energy costs.