Basic materials for various making gangjung, various concentration 0-25.0%(w/v) of coating agent and 0-20.0% of substitutional materials carried out an experiment in sensory evaluation, expansion rate and hardness of substitutional materials. The results are as follows: 1. Added coating agent for improvement of decreasing aroma, arabic gum and dextrin signiffcant from 20.0% to 25.0% compared with others. A good results flavor strength score and hedonic score of added 20.0% arabic gum are highest. 2. Expansion rate is caused by substitutional waxy rice, expansion rate decreased above 20.0% as tapioca above 5.0%, rice above 10.0%, brown waxy rice and wheat flour 15.0%. 3. After flying gangjung of substitutional materials, hardness increase concentration of substitutional materials. Therefore substitutional materials added to tapioca below 5.0%, rice and wheat flour 10.0%, brown waxy rice 15.0% is thought of good.