In the present study, the molecular sieve MCM-41 was synthesized and was modified with chloro solfunic acid groups. The modified MCM-41 leads to more acidic character and better reactivity of it. In this regard, MCM-41 surface modification were done with benzyl alcohol group and sulfonated with chlorosulfonic acid. Identification of catalysts was achieved by the techniques such as small angle XRD, IR, BET, TGA, SEM, elemental analysis and TEM. TEM analysis of the structure showed the hexagonal pattern to approve the mesoporous structure. SEM analysis showed a mixture of spherical and road-shape particles. In addition, BET analysis represents the high porosity and surface area for the modified catalysts. SAXS analysis states that the unit cell parameter of holes is about 4.7 nm. In the next stage, a new method for the synthesis of tetrazole derivatives using the modified MCM-41 in DMF as the solvent. Synthesized compounds were identified using the techniques such as IR, NMR and physical methods. The results showed that MCM-41 modified by benzyl alcohol and chlorosulfunic acid (MCMBSA) has higher efficiency and performance relative to MCM-41 modified by chlorosulfunic acid (MCMSA). Special feature including appropriate efficiency, easy extraction and being compatible with the environment are the advantage of the method. The catalyst recycled 4 times and the recycled catalyst showed good yields.