The present invention relates to a disc loading apparatus that has the capability of simplifying the assembly while improving thinning and reducing the number of components. With a disc loading apparatus according to the present invention, a portion of a top panel of the frame is designed to be a second mounting unit and another portion of the top panel to be a first mounting unit, the upper surface of the second mounting unit is sagged downward more than the lower surface of the first mounting unit, notches are provided appropriately at the steeped unit between the first and the second mounting units, the second mounting unit is a portion of the disc guide, the interlocking mechanism is mounted on the upper surface of the second mounting unit, and the pair of disc detection members is mounted on the lower surface of the first mounting unit, and these detection members are arranged throughout the lower surface of the first mounting unit and the upper surface of the second mounting unit through the notches.