A diskless PC network communication agent system includes a host, a network communication agent, a physical network connecting the network communication agent to the host, and diskless PCs connected to the network communication agent. The network communication agent has network packet filtering and transferring functions so that a virtual private network is established between the network communication agent and the diskless PCs for enabling each diskless PC to use a preboot execution environment communication protocol to catch dynamic host configuration protocol information, to start up network bootstrap, and to request the host for the services of remote installation, boot and access to virtual disk.