An image processing apparatus is provided in which the frequency of undesired delay of the image output can be reduced. The image processing apparatus comprises an image processor for performing a process defined by a parameter on the image data of the received job, a decision portion for deciding a state of the image data of the received job, and a controller for setting a parameter in accordance with the state that is decided by the decision portion if an interval between the received job and the previously received job is longer than a predetermined time, and for setting the parameter that was used in the last job despite the state that is decided by the decision portion if the interval is not longer than the predetermined time.