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CuLaHY zeolite absorbents with different Cu loadings were prepared by the equal volume impregnation method under an air atmosphere. They were characterized by X-ray diffraction (XRD), BET surface area measurement, and X-ray photoelectron spectroscopy (XPS). The crystalline structure and distribution Of Cu2+ and La3+ cations in the cages of the Y zeolite were determined by powder XRD. The performance of adsorption desulfurization for CuLaHY zeolite adsorbents was investigated using a model diesel containing dibenzothiophene (DBT). Results showed that a large amount of Cu from the precursor CuCl, exchanged with the LaHY zeolite and entered the cages of the Y zeolite while a very small amount of Cu from the precursor CuCl2 was highly scattered in the cages of the Y zeolite in the form of CuCl. The La3+ cations and a portion of the Cu2+ cations entered the cages of the Y zeolite and situated at the S-I, sites in the beta cages while another portion of the Cu2+ cations situated firmly at the S-II and S-III sites in the supercages of the Y zeolites. They were coordinated to skeleton-oxygen atoms and water molecules. Cu2+ cations in the supercages can adsorb DBT molecules from the model diesel and thus become centers of adsorption desulfurization. However, naphthalene molecules will result in competitive adsorption with DBT molecules.