The invention discloses a heating power three-level combustion cremator, and relates to the technical field of cremation. The heating power three-level combustion cremator is characterized by comprising a first-time combustion chamber, a second-time combustion chamber and a third-time combustion chamber. The second-time combustion chamber is communicated with the first-time combustion chamber, and the third-time combustion chamber is communicated with the second-time combustion chamber; the first-time combustion chamber comprises a bottom channel and a turbulence channel, and the second-time combustion chamber is arranged on the side portion of the turbulence channel of the first-time combustion chamber; speed reduction fans are arranged on the upper portion and the lower portion inside the second-time combustion chamber, and the third-time combustion chamber is arranged above the second-time combustion chamber; the interior of the third-time combustion chamber is arranged to be in an inverted-conical shape; and the third-time combustion chamber comprises a turbulence chamber on the lower portion and a combustion chamber body on the upper portion. The heating power three-level combustion cremator is reasonable in structure and convenient to use, and the longer smoke staying time can be provided in the small space; meanwhile, it is endured that harmful pollutants are thoroughly burnt, and the phenomenon that the untreated pollutants are discharged into the atmosphere, and consequently, the environment is polluted is avoided; and turbulent mixing is greatly improved, a combustion flow field is more reasonable, and more energy and time are saved.