Abstract: A refuse bag cart is fully collapsible and includes novel means for supporting the mouth of the refuse bag in its fully opened position. Individual rotatable support arms each include novel clamp means which firmly grip opposite sidewalls of the mouth of the refuse bag at the top. The length of each support arm is sized to the bag dimension to provide sidewall support as well as a laterally movable structure to hold the mouth of the bag open. The support arms are rotatable in the horizontal plane so that bags of different circumference may be held fully open. The support arms are further pivotable in the vertical plane. Because the support arms occupy the interior of the bag in their operative position, the vertical pivot allows them to be swung downward into the bag cavity easily and quickly. Over-the-center, locking toggle clamp means are included on each support arm and each clamp has elongate jaws which firmly grip sidewalls of the bag and lock in the closed position.