Abstract: 6-O-monotosyl-deoxy-β-cyclodextrin (6-OTs-β-CD) was prepared by literature method, and analyzed by IR and ¹HNMR. The analytic results show that the goal material is reliable. The inclusion complex was acquired by the reaction of 6-OTs-β-CD and N, N′-diphenyl thiourea with the mole ratio of 2∶1, and then the comprehensive thermal analysis spectrum was used to study the thermal stability of inclusion complex. The adsorption behaviors of the inclusion complex and N, N′-diphenyl thiourea to Th⁴⁺ were studied with the method of visible spectrophotometry. The experimental results indicate that the adsorption equilibrium of inclusion complex is shorten greatly comparing with N, N′-diphenyl thiourea. The best adsorption conditions are as follows: pH=4, shaking for 10 min and the sorbent mass is 0.025 g, the adsorption capacity is 27.46 mg/g, and the adsorption rate is up to 91.5%.