A disc cartridge of the open cover type capable of readily accomplishing takeout and insertion of a disc medium with respect to the cartridge while ensuring easiness of assembling thereof and increased reliability in operation thereof. An upper casing member is formed on a side surface thereof opposite from a shutter with a takeout opening which permits a disc medium to be taken out of a casing therethrough. The casing is mounted thereon with a cover for opening and closing the takeout opening. The cover is provided with support shafts disposed on opposite sides thereof. The upper casing member is provided with guide grooves in which the respective support shafts are slidably and pivotally fitted, to thereby permit the cover to be selectively opened. The cover may be provided with a receiving section for slidably receiving an erasure prevention member therein. The disc cartridge may be provided with a discrimination member for detecting whether takeout of the disc medium has been carried out.