An image forming apparatus, comprising: a photosensitive member which has a rotatable surface; image forming means adapted to form an image on the photosensitive member; a time measuring device adapted to measure information about a rotation time and information about a stop time, the rotation time being a period of time elapsed from a time when the photosensitive member in a stop state starts rotating, the stop time being a period of time elapsed from a time when the photosensitive member in a rotation state stops rotating; a temperature and humidity detecting device adapted to detect information about a temperature and humidity of the image forming apparatus; a fixing device adapted to fix a toner image transferred to a recording material; and a controlling device adapted to control an image forming condition of the image forming means, the controlling device being adapted to determine the image forming condition for a subsequent image formation based on the information about the rotation time, the information about the stop time, the information about the temperature and humidity, and whether an image formation that precedes the subsequent image formation is performed in a single-sided print mode or a double-sided print mode, wherein the single-sided print mode is a mode in which a transfer is performed only on a recording material that has never passed through the fixing device, and the double-sided print mode is a mode in which a transfer is performed on a recording material that has passed through the fixing device, and wherein the image forming condition comprises at least one of a charging bias applied to a charging device and a developing bias applied to a developing device. a photosensitive member which has a rotatable surface; image forming means adapted to form an image on the photosensitive member; a time measuring device adapted to measure information about a rotation time and information about a stop time, the rotation time being a period of time elapsed from a time when the photosensitive member in a stop state starts rotating, the stop time being a period of time elapsed from a time when the photosensitive member in a rotation state stops rotating; a temperature and humidity detecting device adapted to detect information about a temperature and humidity of the image forming apparatus; a fixing device adapted to fix a toner image transferred to a recording material; and a controlling device adapted to control an image forming condition of the image forming means, the controlling device being adapted to determine the image forming condition for a subsequent image formation based on the information about the rotation time, the information about the stop time, the information about the temperature and humidity, and whether an image formation that precedes the subsequent image formation is performed in a single-sided print mode or a double-sided print mode, wherein the single-sided print mode is a mode in which a transfer is performed only on a recording material that has never passed through the fixing device, and the double-sided print mode is a mode in which a transfer is performed on a recording material that has passed through the fixing device, and wherein the image forming condition comprises at least one of a charging bias applied to a charging device and a developing bias applied to a developing device.