End-to-end measurement cannot show clearly the life of packets within a network. This paper proposes the method to distributedly monitor packets at all the routers in the network. We collect packets' information at each router they travel, adjust the timestamp and analyze the collected data to give the detailed view of the lives of packets. We also implement the tool of distributed packet monitoring, which can be used for network engineering and management. We show examples about how our tool works and demonstrate that we can provide the detailed and correct information in many circumstances.