Background: Globally, wasting threatens the lives of 50 million children under-five. In Ethiopia, wasting is not decreasing at the intended rate, but the reason remains unclear. Moreover, Bakadawula Ari district lacks scientific information regarding wasting among children. Objective: This study was conducted to determine the magnitude of wasting and its predictors among under-five children in the district. Methods: A community-based cross-sectional study was conducted from January to March 2022. A multistage sampling technique was used to select 421 children. The data were entered and analyzed by SPSS 26 (Statistical Package for the Social Sciences version 26). Logistic regression analyses were used and presented with crude odds ratio (COR) and adjusted odds ratio (AOR) with their 95% confidence intervals (CI). Results: The prevalence of wasting among children in the study area was 22.6% (95% CI: 18.5-26.8). Fathers with primary education (AOR= 4.48; 95% CI: 1.93-10.39), households with improper solid waste- disposal (AOR= 2.54; 95% CI: 1.11-5.82), not usually sleeping under insecticide-treated bed net (ITN) (AOR=1.79; 95% CI: 1.01-3.19), unacceptable children dietary diversity score (DDS) (AOR= 2.56; 95% CI: 1.28-5.14) and unacceptable household DDS (AOR= 2.26; 95% CI: 1.02-5.00) were predictors of wasting. Conclusions: The prevalence of wasting among children was critically high. Upgrading educational status of fathers, encouraging safe solid waste disposal, ensuring consistent use of ITN, and improving both children and household DDS should be given a due emphasis to reduce wasting in the study area.