Abstract: A trailer hitch cover is disclosed comprising apparatus for protecting the open end of a tube hitch. The hitch comprises a hollow member such as a square hollow bar extending in back of a vehicle, the tube being adapted to receive an arm from a trailer which fits into the tube and is secured therein by means of a hitch pin that passes through the opening in the tube and the arm. The apparatus of the invention comprises a member having an adjustable extension which may be inserted inside of the tube hitch and projects towards the open end of the tube and to which is secured a plug which seals the end of the tube. The adjustable extension has an opening for receiving the hitch pin and permits the exact positioning of the plug in the end of the tube in order to provide a seal therefore.