The invention relates to an O-shaped steel bar connecting structure. The O-shaped steel bar connecting structure comprises two rows of U-shaped steel bars arranged on different concrete components. The two rows of the U-shaped steel bars are oppositely overlapped and crossed to form the O-shaped steel bar structure which is internally provided with a plurality of supporting cushion steel bars and forms anchorage-type connecting through pressure-bearing concrete pouring. According to the O-shaped steel bar connecting structure, a traditional mode and a force-transferring mechanism of steel bar connecting are changed, the width of a wet joint formed by connecting is greatly reduced to be less than half of the width of a non-welding wet joint of a traditional steel bar, steel bar connecting and component jointing are simplified, material using is reduced, engineering cost is reduced, the workload is greatly reduced, construction site quick connecting of factory precast concrete components is achieved, and development of a bridge girder industrial construction technology is promoted.