The objective of this paper is to study the synchronized output regulation of networked dynamic systems with switching topology. In the networked systems being analyzed the state of exosystem is available to the leader nodes, and only the estimated state of exosystem to the follower nodes. A distributed synchronous protocol is proposed to make the estimated state of exosystem synchronize to the state of exosystem by assuming that the switching topology is uniformly connected and leader-rooted. With the estimated state of exosystem, a decentralized state feedback controller is designed for all nodes. At last, a simulation result shows the validity...