Portable Bridging System for Disaster Relief Operations comprises portable structures including foldable long-span beams and portable piers. The foldable beams are made of composite materials and/or aluminium alloy. The structures are lightweight, thus, are easily transported, erected and launched. The beam can span up to 28 meters in a single span. However, with the portable piers, it can be constructed in multiple spans, thus making the portable bridging system more reliable for relief operations.