BackgroundOver 1.7 billion instances of diarrheal illness in children are reported worldwide yearly. Diarrhea was a major cause of death in children, accounting for 9% of all global under-five child deaths in 2021. The objective of this study was to identify the association between hygiene practices and childhood diarrhea among under-five children in Myanmar.MethodThis cross-sectional study was conducted in 16 townships from 8 states and regions of Myanmar. 1207 children between the ages of 6 and 59 months were recruited by multistage random sampling. Data were collected with a preformed questionnaire after participants provided consent. Multiple logistic regressions were administered to determine the factors associated with childhood diarrhea.ResultThis study found that 86 (7.13%) under-five children experienced diarrhea disease. This study identified that children receiving limited hygiene services were 2.85 times (AOR = 2.85, 95% CI: 1.31 to 6.21; p value 0.01) and children without hygiene services were 2.63 times (AOR = 2.63, 95% CI: 1.42 to 4.89; p value 0.01) more likely to have diarrhea disease than those with basic hygiene services. Other factors associated with diarrhea included: fathers who washed their hands less than four steps (AOR = 2.20, 95% CI: 1.29 to 3.74; p value 0.01), families taking more than 15 min to collect water (AOR = 1.77, 95% CI: 1.06 to 2.97; p value 0.03), families sharing toilet usage (AOR = 2.00, 95% CI: 1.15 to 3.48; p value 0.01), mother’s inadequate and problematic hygiene promotion health literacy (AOR = 2.20, 95% CI: 1.24 to 3.90; p value 0.01), houses made of bamboo or lacking floors (AOR = 2.31, 95% CI: 1.38 to 3.89; p value 0.01), families with three or more children (AOR = 1.68, 95% CI: 1.01 to 2.79; p value 0.05) and breastmilk being the primary food after 6 months of age (AOR = 2.07, 95% CI: 1.09 to 3.93; p value 0.03).ConclusionsEnsuring access to basic hygiene services, getting water at home 24 h per day, seven days per week, using private toilets, promoting hygiene health literacy, improving house flooring, family planning and introducing a variety of foods after age 6 months could significantly prevent diarrhea among under-five children in Myanmar. This study underscores the critical role of handwashing facilities in reducing the diarrhea incidence in children.