The invention discloses a multi-pipe group mounting frame comprising two parallel bottom longitudinal beams, wherein a plurality of cross arms perpendicular to the bottom longitudinal beams are arranged between the bottom longitudinal beams, and a plurality of layers of pipe hoops and pipe clamping racks for fixing pipes are arranged on the cross arms; upright posts are fixedly connected to two ends of the cross arms, and the tops of the two upright posts connected to the same cross arm are connected by top cross beams; the top cross beams are fixed between two top longitudinal beams; the pipe hoops are fixed on the cross arms, and the pipe clamping racks are arranged on the pipe hoops. The invention further provides a prefabricating construction method based on BIM (Building Information Modeling) for the mounting frame. Optimal design of the mounting frame is performed by automatically integrating and extracting data via BIM technology, so that the design accuracy is ensured, and meanwhile, modular and standard prefabricating construction of the multi-pipe group mounting frame is also realized; the design, production and construction of the multi-pipe group mounting frame are managed in a unified manner, so that the construction difficulty is reduced, the construction efficiency is improved and the project cost is lowered.