BACKGROUND: Maternal handwashing practice is an important measure to prevent the spreading of childhood disease. Handwashing is still being practiced to a very low extent especially at critical times since the global prevalence of handwashing with soap was estimated at 19% by a systematic review after compiling 42 studies all over the world.

OBJECTIVE: To assess the handwashing practice and its predictors among mothers of children aged 0 to 23 months in Mareka District, south Ethiopia, 2020.

METHOD: A community-based cross-sectional study was conducted with a multistage sampling technique on 520 women having children aged 0 to 23 months in Mareka District. Data were collected by using interviewer-administered pre-tested structured questionnaires. Data were checked for completeness and entered into Epi data entry 4.6.2. The data were exported into SPSS version 22 for analysis with multivariate logistic regression analysis at P < .05.

RESULT: Mothers wash their hands with soap and water after visiting the latrine (27.1%), after cleaning the child’s bottom (28.5%), before cooking (6.2%), before eating (6.9%), and before feeding the child (21.2%). The most important predictors were water availability near the handwashing location with an adjusted odds ratio (AOR) 5.26 (95% CI 1.99-13.69) and soap availability near the handwashing location with AOR 0.40 (95% CI 0.18-0.89) for good handwashing practice.

CONCLUSION: The handwashing practice at critical times was low. The presences of water and soap near the handwashing location were the most important predictors. It is necessary to increase the provision of both water and soap near the handwashing location for improving handwashing with soap and water at key times.