An image forming apparatus includes a laser scanning unit that irradiates a light. A photoconductive medium forms thereon an electrostatic latent image using the light from the laser scanning unit. A developing roller transfers a developer onto the electrostatic latent image formed on the photoconductive medium to develop the electrostatic latent image. A transferring roller forms a transfer nip in tight contact with the photoconductive medium and transfers the developer attached on the photoconductive medium onto a paper passing through the transfer nip. A paper supplying part stacks the paper thereon. A pickup roller picks up the paper stacked on the paper supplying part. A paper edge sensor senses a top edge of the paper picked up by the pickup roller. The paper picked up by the pickup roller is directly supplied toward the transfer nip. A paper moving path is reduced, thereby minimizing the whole size of the image forming apparatus. Also, the number of parts is reduced, thereby decreasing material costs.