The invention discloses a fly ash treatment system based on garbage classification treatment. The system comprises a smoke exhaust pipeline, wherein the smoke inlet end of the smoke exhaust pipeline communicates with the top of an incinerator; the smoke exhaust pipeline is sequentially provided with a waste heat collecting pipe section and a fly ash collecting pipe section along the smoke exhaustdirection, and at least two sections of fly ash collecting sections are sequentially arranged along the fly ash collecting pipe section; the fly ash collecting pipe section is internally provided withan electrode purification module; the end part of the smoke inlet end of the smoke exhaust pipeline is also provided with a bypass pipeline; and an air outlet of the bypass pipeline communicates withthe front end of the fly ash collecting pipe section. By adopting the abovementioned scheme, the electrode purification module is arranged on the fly ash collecting pipe section, so that fly ash accumulation detection is realized. When the flying ash is adhered to the smoke exhaust pipeline, the smoke discharged from the incinerator is directly transmitted to the ash collecting pipe section trough the arranged the bypass pipeline, and the flying ash adhered to the smoke exhaust pipeline is heated by hot gas to fall off and is discharged under the action of strong smoke blowing.