The invention discloses a mansard-roof box wagon, belonging to the technical field of rail wagon manufacturing. The mansard-roof box wagon comprises a coupler buffer device 1, a
bogie 2, a lateral wall 3, an underframe 4, a roof 5, a door 6, an
air brake device 7, windows 8 and an headwall 9; the roof 5 is mansard-shaped; the roof 5 comprises a roof plate 5.1, a ventilator 5.2, a roof camber beam 5.3, a roof side beam 5.4, a roof end camber beam 5.5 and a roof end plate 5.6; the lateral wall is in a plate-
column structure; the underframe 4 is in a grid beam structure; and the headwall 9 is in an in-line beam structure. The mansard-roof box wagon disclosed by the invention has the advantages of sufficiently utilizing the locomotive gauge, increasing the area of cross section inside the wagon body, having high space
utilization rate, effectively shortening the wagon length, reducing the
dead weight of the wagon, improving the loading environment of cargos in the wagon, meeting the mechanical working requirements of forklifts, and the like, improving the loading and unloading efficiency, ensuring that the wagon strength and rigidity meet standard requirements and
carrying capacity of the wagon is large, increasing the variety of transportable cargos, improving the comprehensive freight capacity and being capable of meeting the development requirements of rail freight after separation of freight and passenger line.