In this study, the activity of amylase was measured to discuss whether Nippon hawthorn (Crataegus cuneata) and Chinese hawthorn (Crataegus pinnatifida) could promote digestion by improving the activity of amylase. After the preparation of hawthorn extracts at different temperatures (30,0, 80℃), the intestinal environment was simulated and the effects of hawthorn water extracts on amylase were investigated at different reaction temperatures (25,7, 45℃), different pH (6.5,6.8), and ion conditions (C₂O2-₄, Zn²⁺). The results demonstrated that the activity of amylase could be increased by hawthorn extracts at each reaction temperature and pH. Among them, the extracts from Chinese hawthorn under 60℃ showed the strongest promoting effect on activity of amylase under the reaction conditions of 37℃ and pH 6.5. C₂O2-₄ had the promoting effect on the reaction of amylase with the Chinese hawthorn, while Zn²⁺ showed the inhibitory effect of extracts from Nippon hawthorn and Chinese hawthorn on promotion of amylase activity.