Abstract: A waste compactor comprising a cabinet having an extendible ram assembly mounted adjacent the upper end thereof and a removable dolly associated with the lower end thereof. The dolly is adapted to support a vertically elongated support device which is adapted to be inserted into the interior of a disposable flexible bag for supporting the bag in an open and upright position for permitting trash to be deposited therein when the support device and bag is disposed on the dolly and positioned under the ram assembly. The support device also acts as a liner for protecting the bag. A chute is swingably mounted on the cabinet for permitting waste to be deposited into the bag. The chute is movable into a closed position wherein it substantially closes the front wall of the cabinet and, when in the closed position, coacts with a safety device to permit energization of the ram assembly. The safety device prevents actuation of the ram assembly when the chute is open or when the dolly is removed from the cabinet.