Bill authentication method and bill authentication system

An embodiment of the invention provides a bill authentication method and a bill authentication system, which are used for authenticating whether a user is legal to enjoy video electronic products or not and guaranteeing rights and interests of an operator and a content provider. The method includes the steps of creating a session between a digital television receiving terminal and a video on demand system through request and transmitting bill information and relevant video information ordered by the user to the video on demand system; transmitting the bill information to a bill management system by the video on demand system; and authenticating whether a bill is legal or not by the bill management system prior to correspondingly handling according to an authentication result. By the aid of the method, whether the user is legal or not can be authenticated extremely safely and reliably, only a rightful bill holder can be entitled to use the bill, otherwise, using the bill is determined illegally, and only the user successfully authenticated can enjoy the service, so that the rights and interests of the legal user, the operator and the content provider are guaranteed.