Food sensitization is common among children, some studies show that the proportion is more than 20%. Food sensitization affects the health of children as it causes post-meal signs that affect one or all organs in the body, in addition to sensitization also affects the nutritional status of children. TUY so, currently in our country there are no studies to determine food sensitivity in children. In order to determine the rate of sensitive children under 5 years old, through which proposed intervention solutions, the author conducted a cross-sectional descriptive study of 497 children under 5 years old at Hoa Mai kindergarten, Cau Giay , Hanoi. The research results show that: 9.26% of children have been sensitive to food, the percentage of foods that are susceptible is as follows: Nuts: peanuts 1.4%, sesame 1.61%, soybeans 2.41%, other seeds 0.6%. Hypersensitivity to chicken eggs 3.02%, egg-containing food is 2.41%, susceptibility to cow's milk is 2.01%, with egg-containing foods is 2.41%, sensitive to cereal products (wheat flour, bread, shrimp noodles): 1.41%, susceptible to fish 1.81%, with crustaceans 3.82%.