Disc recording/reproducing apparatus

A disc recording/reproducing apparatus includes a main frame, a disc cartridge including a case with an opening on a bottom thereof to expose a disc-type recording medium and a window on a sidewall thereof, a shutter mounted in the case to expose and cover the opening, a rotary wheel operating in association with the shutter, and a latch unit formed at one side of the case to control rotation of the rotary wheel, a tray mounting the disc cartridge and moving with respect to the main frame, a shutter opening/closing unit connected to one side of the main frame, a rack member of a cantilever type contacting with the rotary wheel , and first and second connection ribs connected to a static part of the shutter opening/closing unit, and a cam guiding the rack member distanced in relation to or from the latch unit, during shutter opening/closing operations.