In order to cause a management server to execute a process desired by a user and to be shared by a plurality of users, an image processing apparatus capable of communicating with the management server includes a scanner inputting image data, an authentication information input unit inputting information necessary for authenticating a user, an authentication information send unit for transmitting the input authentication information to the management server, an additional function list receiver receiving from the management server, in response to the transmission of the authentication information, an additional function list for specifying an additional function registered in association with the user among the additional functions executed by the management server, an additional function selector accepting designation of the additional function, and an additional function select information transmitter transmitting the specified additional function and the input image data to the management server.