Water-soluble anti-hypertension drug Captopril was incorporated in Si-MCM-41 channel by using impregnation wetness method, the mass fraction of drug[m(drug)/m(Si-MCM-41)] was 33.99%. Captopril/Si-MCM-41 assembly was characterized by XRD, IR, UV-visible technique. The sustained release profile was observed by soaking the assembly in vitro simulated stomach fluid. The results suggest that a Captopril/Si-MCM-41 sustained release system was obtained.