The invention provides a method for constructing an authentication system, and belongs to the technical field of application service authentication. The method comprises the following steps: configuring hardware data to authentication equipment, and configuring authentication service with a verification function of the hardware data to the authentication equipment; and isolating an authenticationnetwork of the authentication device from an application network of an application service interacting with the authentication service, obtaining the authentication service in an execution state in the authentication network by using the verification function of the hardware data, and forming an authentication system through the authentication device corresponding to the authentication service inthe execution state. An application server and an application network do not need to be modified, the hardware cost and the deployment cost are low, and the authentication system has high safety and high availability and has integrity and consistency relative to the pre-configuration condition.