An image forming apparatus includes an image forming section to form a toner image and transfer the toner image to a recording medium and a fixing section to heat the recording medium transferred with the toner image and further an image analyzing section to extract a density value or a size value of an imaging object included in an image, and a temperature determining section to determine a minimum fixing temperature based on the density value or size value of the imaging object included in a page image. The temperature determining section determines the minimum fixing temperature to be lower when a highest one of the density values is lower than when the highest value is higher or determines the minimum fixing temperature to be lower when a largest one of the size values is smaller than when the largest size value is larger.