The present invention provides a content distribution system which assures reliability of content. Permitted-user information 11 corresponding to a user who is permitted to use content 10 to be distributed is associated with the content 10. In the case where user specific information 36a which specifies a user 2 and the permitted-user information 11 do not have a predetermined relation, a user terminal 3 transmits the user specific information 36a and the permitted-user information 11 to a server 4. The server 4 generates user-related information 41a in which the received user specific information 36a is set as a distribution destination and the permitted-user information 11 is set as a distributor, generates new permitted-user information so as to have the predetermined relation with the user specific information 36a, and provides the new permitted-user information to the user terminal 3. The user terminal 3 which obtains the new permitted-user information changes the permitted-user information 11 to the new permitted-user information.