Dye wastewater has attracted significant attention because of its wide pH range and high content of color.In this study, the coagulation performances of cucurbit[8]uril (CB[8]) in the removal of color from acid red 1 (AR1), orange Ⅱ (OII), and congo red (CR) dye wastewaters were investigated.Experimental results showed that color removal rates of greater than 95% for AR1, OⅡ and CR were achieved at pH 6.0, when the dosage of CB [8] were i.51, 3.01 and 0.38 mmol· L-1, respectively.Under identical conditions, AR1 and CR, with larger molecular weight and more active hydroxyl (-OH) and amino (-NH2) groups, had higher color removal efficiencies.Moreover, the removal rates of AR1, OⅡ and CR increased gradually with the increase in ionic strength.Such an increase may be related to the decreased thickness of the surface solvent membrane surrounding the dye colloids at high ionic strength.FT-IR spectra demonstrated that new bonds or functional groups did not form during coagulation, which indicated that the removal ofAR1, OⅡ and CR was primarily a physical process.Further studies showed that the hydrogen bonds and inclusion complexes formed between CB[8] and ARI, OⅡ and CR mainly contributed to the removal of color in coagulation.