According to an embodiment of the present invention, an image forming apparatus includes a toner image carrier that carries a toner image, a toner image detection sensor that detects a reference toner image on the toner image carrier, a temperature sensor that detects a temperature in the apparatus, and storage section for storing a correlation between each temperature and a drive value for the toner image detection sensor, in which calibration of the toner image detection sensor is performed by acquiring a corresponding drive value from the storage section based on the temperature measured by the temperature sensor and driving the toner image detection sensor at the acquired drive value.