A tow-bar mounting system and method for removable and adjustable mounting of a variety of accessories upon a tow-bar structure such as a vehicle trailer hitch or bumper, having clamping mount units and inserting mount units, each clamping mount unit having a plain-angled subunit with a hinging tab and a fastening hole, and a mounting angled subunit with a hinging slot, a fastening tab, dual extended mounting arms, and dual accessory mounting holes, and each inserting mount unit having an inserting body, a single extended mounting arm, and dual accessory mounting holes.