Sol Gel expansion method was used for the first time to study reaction of granite aggregates with alkali. The results show that Sol Gel expansion method is sensitive to distinguish different reactivity of aggregates by direct reaction between alkali and aggregates. So this method will be developed into a new chemical test. Depending on deformation of quartz caused by different geologic stress and erosion of minerals caused in different efflorescent condition, granite could be different in reactivity with alkali.