The invention relates to a treatment method used for molecular sieve calcination tail gas and performed in the following equipment, wherein the equipment comprises a quenching tower, an absorption tower having a bottom portion tower tray, and a washing liquid storage tank, wherein the bottom portion tower tray comprises an obliquely-arranged diversion plate. The method comprises that molecular sieve calcination tail gas and a first washing liquid are subjected to first contact in the quenching tower, wherein the first washing liquid comprises washing liquids from the ejection device of the quenching tower and the washing liquid storage tank; the contacting gas stream, a filler in the filler layer of the tail gas absorption tower, and a second washing liquid are subjected to second contact in the filler layer of the tail gas absorption tower; and the first washing liquid being subjected to the first contact and the second washing liquid being subjected to the second contact are mixed on the bottom portion of the absorption tower, and the obtained mixed is circulated so as to be adopted as the first and/or second washing liquid. According to the present invention, the washing liquid is used to be subjected to two circulations in the equipment, and the obliquely-arranged diversion plate is used, such that the washing liquid utilization rate is improved, the waste heat of the molecular sieve calcination tail gas can be effectively recovered, and the pollutants contained in the molecular sieve calcination tail gas can be removed.