Malnutrition continues to be a long-term year-round phenomenon, threatening under 5 children unacceptably the most. It is responsible for 25,000 children’s hospitalization per month and nearly 50% of all under 5 mortalities in Ethiopia. The national burden of SAM highlights the importance of addressing predictors of recovery rates. The presence of complications like infections, septic shock, hypoglycemia, and pneumonia may guard the recovery rate. Over the past 10 years (2005 to 2016), the prevalence of wasting had shown little change (from 11 to 10%), with a moderate reduction of stunting from 47% to 39%. Objective This study was aim to describe the treatment outcome and predictors of recovery from SAM among 6 to 59 months old children admitted to Hawassa university comprehensive specialized hospital from August 2020 to August 2021. Methodology An institution-based retrospective cohort study was implemented in children between 6 months and 5 years of age with SAM admitted to HUCSH from a period of august 2020- august 2021. Data were collected from the patients’ charts by using a structured questionnaire. Data was entered and analyzed using the Statistical package for social science (SPSS 25). The output of both bivariate and multivariate logistic regression analysis was presented using an odds ratio and 95% confidence interval. A p-value of less than 0.05 was taken as statistically significant. Results Among a total study case of 241 children, 192(79.7%) were recovered, 15(6.2%) died, and 20(8.3%) defaulters. The mean (±SD) weight gain and hospital stays were 10.1 (±3.36) g/kg/day and 17.8 (±4.87) days respectively. The majority of the children, 155(64.3%) had non-edematous malnutrition. 10(66.7%) of the death occurred within the first week of admission and 188(78.1%) discharged improved within the first four weeks of admission. The independent predictors of recovery rate were: the presence of pneumonia (AOR=6.565, 95% CI-1.508-28.90), hypovolemic shock (AOR=0.054, 95% CI=0.005-0.559), both pneumonia and gastroenteritis (AOR=4,463, 95% CI=1,219-16.34), getting third-line antibiotics (AOR=0.233, 95% CI=0.100-0.539), fourth-line antibiotics (AOR=0.154, 95% CI=0.062- 0.327) and hospital stay more than 28 days (AOR=0.119, 95% CI=0.290-0.490). Conclusion The finding of this study attested that recovery and death rates are within the national standard. As much of the death occurred within the first week of admission, due attention should be given to SAM patients since the first minutes of arrival. Reduction of length of the hospital stays, and early recognition and management of complications have been unveiled to further upgrade the recovery rate.