We studied the factors affecting the framework aluminium distribution in the ZSM-5 structure by hydrothermal treatment under different conditions. A1MASNMR, XPS and chemical analysis revealed that with steaming at lower water vapor pressure, the framework aluminium located at the external surface is less stable. Steaming at higher water vapor pressure is beneficial in removing the framework A1 in HZSM-5, and especially helpful in removing that located at the internal surface of HZSM-5. By changing steaming conditions, one may control the framework aluminium distribution in the HZSM-5 structure.