The utility model discloses a remote network monitoring system. The remote network monitoring system comprises a number of network cameras, a passive optical splitter, an optical line terminal device, a network switch and a server, wherein a number of network cameras and the passive optical splitter are arranged outside an information computer room, and the optical line terminal device, the network switch and the server are arranged in the information computer room. Each network camera is provided with an optical fiber interface which carries out communication based on an EPON or GPON network protocol. The passive optical splitter comprises an input end and an output end. Each input end is connected with the optical fiber interface of a network camera, and the output end is connected with the input end of the optical line terminal device arranged in the information computer room. The output end of the optical line terminal device is connected with the input end of the network switch. The output end of the network switch is connected with the server. The communication interface of each network camera uses a PON interface, so that the input end of the optical line terminal device can be connected with a core optical fiber which goes out of the information computer room to be connected with the passive optical splitter outside the information computer room. The remote network monitoring system provided by the utility model has the advantages of simple and reasonable design, convenient use, optical fiber saving, low cost and convenient wide popularization.