An image forming apparatus capable of preventing toner fusion between recording sheets, with a construction that does not require increase in cost and size of the apparatus and does not unduly lower productivity, to thereby offer high usability. For image formation on plural pieces of recording sheets, a CPU controls a recording sheet conveyance interval for a first set based on a detected amount of toner used for the image formation on each page, stores the toner use amounts for respective pages of the first set into a RAM, and controls the recording sheet conveyance interval for second and subsequent sets based on the toner use amount stored in the RAM for each page.