Objects are 209 mothers who have under-five-year children at Dong Ba hamlet, Binh Hoa ward, Thuan An district, Binh Duong province, in march 2009 by interviewing. Result: 37.32% of mothers have good knowledge, 77.03% of mothers have good attitude, 84.69% of mothers have good practice on prevention of acute diarrhea and 62.68% of mothers have good knowledge, 10.53% of mothers have good attitude, 87.08% of mothers have good practice on management of acute diarrhea.