The common channel and culvert structures cannot meet the design requirements in most case when the urban channel structure and the natural gas line cannot avoid each other. Combined with an engineering case, a channel structure of frame bridge is designed to adapt the design conditions. By designing the frame bridge, the displacement of the structural baseboard is controlled, and the internal force is transferred to the pile foundation to make the natural gas pipeline below it no longer subjected to the pressure from the baseboard stress of superstructure and to guarantee its safe operation. At the same time, the baseboard is designed as a "vertical and horizontal beam" system structure, which increases the spanning capacity of the frame bridge and ensures the safe distance between the pile foundation and the natural gas pipeline. The structure is economical and beautiful, safe and reliable, which provides a reference for the similar designs.