In an information processing system which includes a transmitter terminal and an E-mail transmission control apparatus, the transmitter terminal sets an application classification of an E-mail to be transmitted, and transmits the E-mail to which the set application classification has been added, to the E-mail transmission control apparatus. Further, the E-mail transmission control apparatus receives the E-mail to which the application classification has been added, from the transmitter terminal, identifies, from approval request information in which the application classification and an approval request destination are made corresponding to each other, the approval request destination corresponding to the application classification added to the received E-mail, and transmits an approval request to the identified approval request destination.