A simplified device is provided for fixing a floating chassis to a main chassis. The floating chassis fixing device has a control member movably mounted on one side of the floating chassis, a push-in member for transferring a disc to a playing position and a disc guide for guiding the disc to the playing position, which are coupled to the control member such that they are interlocked. When no disc is loaded, the control member, the push-in member and the disc guide are engaged with the main chassis to fix the floating chassis to the main chassis.