BackgroundHand washing is a simple, convenient, and cost-effective means to limit the transmission of communicable diseases. Improving the practice of hand washing is vital to decrease hygiene-related morbidity and mortality, particularly in developing countries. As such, this study aimed to assess knowledge, attitudes, and practices of hand washing among schoolchildren in Aderash primary school, Yirgalem town.MethodsA cross-sectional study was conducted on 279 schoolchildren from March to May 2019. A pretested structured questionnaire was applied to collect all relevant information using simple random sampling. Data entry and clearance was done with Epi-Info version 7 and exported to SPSS version 20 for analysis. Adjusted ORs with 95% CI were used to assess statistically significant variables (p<0.05).ResultsOverall, 62.7% of schoolchildren had adequate knowledge of hand washing, 61.3% exhibited positive attitudes toward hand washing and 39.1% had good hand-washing practices. Over three quarters (89%) of them had good knowledge of washing hands with soap. About 24%, 56.6%, 9.3%, 6.5%, and 3.6% of children reported washing hands after defecation, before meals, after meals, after work, and after play, respectively. In addition, 73.8% of them reported washing hands with soap if their hands looked dirty or smelled bad. Urban dwelling increased knowledge of hand washing of 1.3-fold (95% CI 1.2–2.85).ConclusionEven though >60% of children had adequate knowledge and exhibited positive attitudes toward hand washing, proper hand-washing practices was <40%. Therefore, much effort should be directed toward improving children’s understanding of the benefits of proper hand washing in schools.