Network separation system and method thereof

Disclosed are a network separation system using a web client and a method for the same. According to one aspect embodiment of the present invention, a network separation system using a web client connectable to an external network and an internal network includes a host operating system; a web client including a web browsing module connectable to only the external network; and at least one local application directly executable on the host operating system, connectable to the internal network, and not connectable to the external network. The web client is directly executed on the host operating system by an execution request inputted through an UI of the host operating system, and the execution results are outputted on a desktop UI of the host operating system.