A first embodiment of a safety rail for a folding scaffolding cart comprises a single hollow metal tube having two longitudinal ends and shaped to have three smooth 90 degree bends to fit diagonal posts of a folding scaffold. The portable scaffolding cart is a folding platform supported by a rectangular framework having four vertical tube supports with one support tube at each corner. Each support tube has lockable wheels. The vertical supports extend above the platform. The safety rail of the platform connects in an overlapping arrangement to the supports. Alternatively, self-tapping screw fasteners can secure the safety rail. The safety rail is a single shaped tube. Three smooth 90 degree bends in the safety rail allow it to extend upward from a first support, around the perimeter of the platform and back down to a diagonal second support. The safety rail is circular in cross-section, and has a slightly larger diameter than the diameter of the scaffold posts such that each longitudinal end is slotted and sleeved over the first and second diagonal scaffold supports and optionally secured by fasteners. A second embodiment of a safety rail is U-shaped to fit the rear posts of the folding scaffold cart.