In a content distribution method, two or more certification marks (130) are produced for the content to be delivered, each of the certification marks containing a temporary access information item defining an accessing right to the content. Each of the certification marks is distributed to a user at a shop. In a content delivery server, two or more content delivery information items are stored in association with the content, each of the delivery information items containing said temporary access information item. A network device (120) reads the temporary access information item from the certification mark purchased by the user. The network device accesses the content delivery server (110) using the temporary access information item, and receives the content from the content delivery server.