Anemia is a major public health concern among children aged <5 years in the Lao People's Democratic Republic. Thus far, no study has determined the factors associated with anemia among children aged <5 years in the Lao People's Democratic Republic using a nationwide representative sample. Therefore, this study aimed to evaluate the prevalence of anemia and its associated factors with multilevel variations among children aged 6-59 months. This quantitative, cross-sectional study used a nationally representative sample from the Lao Social Indicator Survey II, 2017. Children aged 6-59 months tested for anemia were included in this study through multistage sampling approaches. Anemia was defined as a hemoglobin level of <11.0 g/dL. Multilevel binary logistic regression analyses were used to determine the adjusted effect of the factors associated with anemia. Among the 5,087 children included, the overall prevalence of anemia was 43.0%. Three factors were associated with higher odds of developing anemia-male sex (adjusted odds ratio, 1.16; 95% confidence interval, 1.01-1.34), underweight (adjusted odds ratio, 1.30; 95% confidence interval, 1.09-1.55), and residence in central provinces (adjusted odds ratio, 1.59; 95% confidence interval, 1.30-1.95) and southern provinces (adjusted odds ratio, 1.42; 95% confidence interval, 1.11-1.81). However, the other three factors-age, educational level of the household head, and Hmong-Mien ethnicity-were inversely associated with anemia. To resolve the problem regarding the severity of the anemia among children aged <5 years in the Lao People's Democratic Republic. Our findings highlight the need for designing an effective approach to address each factor associated with childhood anemia. Interventions should focus on the prevention of childhood anemia, which is considered a major priority of public health intervention in the Lao People's Democratic Republic.