Abstract: A digital network video recorder (NVR) and a monitoring system thereof are provided. The NVR features low cost and high stability and is easy to install and use. The NVR receives video/audio data from a network and provides functions of such as the real-time monitoring, recording, and searching/playback operations. The NVR comprises a network module, a storage module, an input/output module and a control module. The network module serves as an interface between the NVR and the network. The storage module stores the video/audio data received from the network and provides the stored video/audio data. The input/output module receives instructions from a user and provides a video playback operation. The control module controls the reception, storage, searching, and playback of the video/audio data.