In a pull printing system, it is possible to perform an alternate print with appropriate security and in consideration of loads on a server while securing convenience of the user requesting a third party for the alternate print. An image processing apparatus in the pull printing system comprises a user authentication unit configured to confirm authority of an alternate process to a first user during login, a bibliographic information managing unit configured to acquire bibliographic information of print data stored in a storage server by a second user from a bibliographic information server for displaying the print data corresponding to the second user and a log information managing unit configured to acquire a log of an operation of the alternate process executed by the first user to the print data corresponding to the second user.