An image forming apparatus judges whether the number of pages to print exceeds the number as a reference to judge whether to print many pages based on the setting of a confidential document print job, when receiving the print job. When the number of pages to print exceeds the reference number, the image forming apparatus ejects printed paper sheets to a housing box having a key unit to lock not to be taken out from the main body together with printed confidential documents. When the number of pages to print does not exceed the reference number, the apparatus performs a private print which starts printing and ejecting printed paper sheets to the paper eject unit after receiving an instruction from a user.