Provided are a device and method for controlling a paper interval in a paper feeder of an image forming apparatus, and an image forming apparatus including the device. The device includes: a leading edge sensor configured to detect a leading edge of a sheet of paper when the sheet of paper is picked up and fed as a printing medium; a feed unit configured to accelerate the sheet of paper; and a control unit. If the sheet of paper arrives late at a paper sensing position of the leading edge sensor, the control unit measures a travel time during which the sheet of paper is fed to the paper sensing position, and according to the measured travel time, the control unit varies a time point at which the sheet of paper starts to be accelerated.