The invention discloses a sludge reduction treatment system which comprises a first barrel, a second barrel and a feed pipe, wherein an outlet end of the feed pipe is correspondingly arranged above the first barrel; sewage to be treated flows into the first barrel through the feed pipe; a plurality of first filtration windows are arranged in a side wall of the first barrel; a sludge discharge pipeis communicated with and arranged at the bottom of the first barrel; the first barrel is sleeved by the second barrel; a filtration cavity with an opening in the upper end is defined by the second barrel and the first barrel; a plurality of second filtration windows are arranged in a side wall of the second barrel; a wastewater pool is correspondingly arranged below the second barrel; two-stage filtration of the sewage has the advantages that part of sludge and water can be quickly separated in a smaller container through the first filtration windows with larger pore sizes and then fine filtration is accomplished by the filtration cavity with a larger volume; the two-stage filtration avoids the problems of easy blocking and easy accumulation due to slow treatment in the traditional singlefiltration; and the working efficiency of the system is significantly improved.