The invention is mainly used for a technology of oblique-pulling buckling and hanging of main arch rib cantilever splicing of a steel pipe concrete arch bridge, and particularly relates to an arch rib buckling and hanging installing structure of a steel pipe arch bridge. A main arch steel pipe of the steel pipe arch bridge is provided with a hoop system, the hoop system comprises two symmetrical semicircular hoop units, the semicircular hoop units are arranged on an upper layer arch rib, a semicircular wrapping plate directly wraps the main arch steel pipe, connecting plates are arranged on the two sides of the semicircular wrapping plate to perform bolted connection of two semicircular hoop units, the connecting plates are provided with bolt pin holes, the bolt pin holes enable an anchor box to be connected with a hoop through pin shafts, and a buckling and hanging cable is anchored into the anchor box. The installing operation is simple and convenient, a temporary buckling point of the steel pipe arch bridge can be installed in a time-saving and labor-saving mode, construction operations such as welding of lifting lugs to a main arch rib are avoided, and the influences, such as unevenness of stress to a main arch, which are caused by residual stress and the like resulting from welding are reduced. The arch rib buckling and hanging installing structure of the steel pipe arch bridge has the advantages of being reasonable in structural design, favorable for structural safety and stability, simple to operate and low in construction cost.