NaY/Beta was firstly modified using two ion-exchanged and two calcinations method to prepare CeY/Beta and CaY/Beta composite molecular sieve, which were characterized by means of XRD and ICP-MS. Static adsorption experiments were carried out to study the adsorption of organic thiophene and quinoline. The desulphurization and denitrogenation adsorption effect of the modified molecular sieve was enhanced greatly, and CeY/Beta molecular sieve exhibited better performance in the desulphurization rate and denitrogenation rate.