An unwrapping apparatus unwraps a slide pack wrapped with a wrapping sheet to obtain a slide contained therein. As paired rollers forward the slide pack, a squeezing member squeezes the slide backward within an unsealed space in the slide pack to form a wide cut allowance at the front edge of the slide pack. After the slide reaches the rear end of the unsealed space, nip pressure applied to the slide pack by the paired rollers is reduced to further forward the slide pack to a predetermined position. At the predetermined position, a cutter partially cuts the cut allowance to form a slit thereon. Then, the slide pack is transferred back by the paired rollers under a raised nip pressure which is sufficient to squeeze the slide out from the slit. Accordingly, the slide will be gradually separated from the wrapping sheet.