The invention discloses a local area network website security architecture system, which comprises a router, a local network area firewall, a demilitarized zone (DMZ), a department subnet zone and a virtual local area network (VLAN) privacy zone, wherein the DMZ comprises a local area network core switch, a local area network switch, a server and a VLAN zone switch; each of the department subnet zone and the VLAN privacy zone comprises at least one computer; the server is connected with a local area network sequentially by the local area network core switch, the local area network firewall and the router; the department subnet zone is connected with the local area network core switch by the local area network switch; and the VLAN privacy zone is connected with the server by the VLAN zone switch. The local area network website security architecture system has the advantages of physically disconnecting the zones of the local area network from the privacy zone in the local area network without influencing the server access, maintenance and data updating of the VLAN zone of a research and development department as well as the website access of a small number of staff of other departments in the local area network, and simultaneously ensuring the security of websites in the local area network.