Depending on processing to be executed, the processing is prevented from being restricted even if a particular image is included in image data. There is provided an image processing apparatus comprising an authentication section 67 which distinguishes a user; a particular-image judgment section 63 which detects particular images from inputted image data and judges whether or not the number of the particular images exceeds a threshold; and a threshold determination section 66 which determines a threshold according to the user and processing to be executed; and a control section 7 which restricts the processing to be executed when the number of the particular images exceeds the threshold. Depending on the importance degree of the security of the processing to be executed, the threshold determination section 66 lowers the threshold as the importance degree is higher and raises the threshold as the importance degree is lower. Furthermore, the threshold is raised in the case of a registered user and lowered in the case of an unregistered user.