This paper introduces the composition of the moving mold frame bridge making machine (undercarriage type), which mainly consists of the mold frame support system, main beam truss system, model system and hydraulic system. And the construction technology of mold frame construction, inner mold construction, mold frame stripping and mold frame moving to the next hole, and corresponding measures are put forward according to the construction difficulties. The front fulcrum of the moving mold frame bridge-building machine is generally located on the bull leg or temporary support pier, and the back fulcrum has different forms according to different construction conditions.