The invention relates to a single-boiler-barrel transversely-arranging type chain grate stoker spraying and denitration corner-tube boiler. The single-boiler-barrel transversely-arranging type chain grate stoker spraying and denitration corner-tube boiler comprises a boiler body and a chain grate stoker part, wherein the chain grate stoker part is arranged at the bottom of the boiler body; the single-boiler-barrel transversely-arranging type chain grate stoker spraying and denitration corner-tube boiler is characterized in that the boiler body 1 is provided with a broiler water circulating mechanism and is composed of a channel rear-wall water cooling wall 30, and an upper collection box 18 and a lower collection box 33 of a deposition chamber; the boiler body 1 is provided with a spraying and denitration cyclone separation sedimentation device which is composed of a denitration and spraying pipe 28, a denitration nozzle 24, a denitration agent supplying device 35, an upper sedimentation separation chamber 21 and a lower sedimentation separation chamber 29. The single-boiler-barrel transversely-arranging type chain grate stoker spraying and denitration corner-tube boiler has the characteristics that the problems that the heated area is small is solved, outlet flue gas of a hearth does not directly wash a flag type heated surface snake-shaped pipe, the abrasion is reduced, the service life of the broiler is prolonged, the number of times of maintaining is reduced, the emission of nitric oxide is reduced, the air pollution is reduced, the heat efficiency is improved, the energy is saved and the boiler is environmentally friendly and safe and the like.