A VPN service management system enabling a customer to rapidly and easily change a VPN service condition, that is, a VPN service management system for managing a VPN service for a communication network provided with a customer network and a provider network and having a VPN service manager for managing a VPN service for a provider network and a VPN service agent for managing a VPN service for a customer network. The VPN service manager changes the VPN service condition in real time in accordance with an operation status of the customer network in cooperation with the VPN service agent.