The utility model discloses a radiant suspension combustion boiler. A bottom has a combustion chamber, top of which is provided connectedly with flues communicating with a chimney at top of the boiler; exteriors of the flues and the combustion chamber are a water cavity; the flue is provided serially connectedly with a plurality of smoke box layers, which are connected via staggeredly arranged flues; the lowest smoke box layer is provided with a dust collection box therebelow; bottom of the lowest smoke box layer communicates with the dust collection box via a plurality of built-in dust removal pipes; flues for communicating the lowest layer of smoke boxes with above layers are positioned by the perforating method in each built-in dust removal pipe with spiral blades provided between inner wall of each built-in dust removal pipe and outer wall of each flue. When the utility model is being used, the spiral blades in the built-in dust removal pipes can reduce the flow speed of combustion flue gas passing through the built-in dust removal pipes so that contained impurities will fall into the dust collection box connected below the built-in dust removal pipes, thereby attaining the objective of dust removal and flue gas purification.