The influence of Al2O3 on alkali content in concrete pore solution was investigated, Al2O3 was added into concrete by bauxite. The quartz glass as active aggregate was dipped in the NaOH solution with Al3+ and without Al3+ respectively. The morphology of the products was observed by scanning electron microscope, the element composition was analyzed by Energy analyzer and the mineral composition was measured by X-ray diffractometer. The results showed that alkali content in pore solution can be reduced effectively by Al2O3. The more content of Al2O3, the lower alkali content in pore solution. The existence of Al3+ changed the ASR products. The products inclined to crystal rather than gel and zeolite was formed. Therefore, the decrease of alkali content in pore solution and transformation of ASR products were the reasons of the substance containing aluminum inhibition ASR.