Diarrhea is the important issue of public health is interested in developing countries. This is the disease incidence and high mortality rates. Diarrhea is also an important factor causing malnutrition and delayed growth in children. Objective: To determine the relationship between the factors (the children, their mother, living environment) with diarrhea in children under 5 years in Tien Giang province. Research Method: Cross-sectional study Results: Factors such as careers and educational level mother, geographic factor, toilets, hand washing habits of the children, how to drink water when they have been diarrhea are related to diarrhea. This difference is statistically significant with p 0.05. Conclusion: Educational level and occupation mother, geography, toilets, hand washing habits of the children, how to drink water when diarrhea are clear related to diarrhea.