Prior to the hydrothermal synthesis, thermal activation of the very chemically inert kaolin is important. In the first step shown in Scheme 2, crystalline kaolin is converted to amorphous, but chemically reactive metakaolin by dehydroxylation process at high temperature under air. In the next two steps, hydrothermal synthesis of zeolite A from both raw and purified kaolin have been conducted. In this, we tried to study the effect of different synthesis parameters on the crystallinity and shape of the zeolite A crystals. Step 2 in Scheme 2 consists of the optimization of the gel formation parameters including NaOH concentration, temperature and time of aging. Finally step 3 involves the hydrothermal synthesis. The final solids are washed and dried overnight before characterization.