An image forming apparatus includes: a reception part that receives specification of a print mode and specification of a sheet type to be used for printing; a sheet supply part that sends a sheet to a sheet conveyance path; a detection part that detects a type of a sheet sent to the sheet conveyance path; and a hardware processor that controls a printing operation, wherein when a sheet type received by the reception part is a type for which printing in the print mode received by the reception part is allowed, the sheet supply part sends a sheet to the sheet conveyance path, the hardware processor determines whether or not the print mode received by the reception part is a prohibition mode, when it is determined that the print mode is the prohibition mode, the detection part detects a type of a sheet sent to the sheet conveyance path.