An image forming apparatus includes a hand detection sensor that detects a hand within a predetermined range from a grasping part of a sheet feeding cassette, a locking mechanism capable of locking the sheet feeding cassette in a closed state with respect to the image forming apparatus body, and an operation control unit that operates the locking mechanism to lock the sheet feeding cassette when the hand is detected by the hand detection sensor during the execution of a printing process in an image forming apparatus body, interrupts the printing process after the locking, and releases the locking by the locking mechanism after the interruption.