BackgroundClient satisfaction reflects the gap between the expected service and the experience of the services from the client’s point of view. As patient satisfaction is considered to be a healthcare outcome and predictor of treatment utilization and adherence to the care and support, assessment of the level of patient satisfaction is vital.ObjectiveTo assess satisfaction of outpatient service and its associated factors toward the health service given among outpatients at Jimma medical center, southern western Ethiopia, 2019.MethodsAn institutional-based cross-sectional study design was employed at Jimma Medical center from May 1 to May 30, 2019 GC. The respondents were selected by systematic random sampling method. The data were cleaned, coded, interred into EPI data version 3.1 and transferred and analyzed using SPSS version 23. Descriptive statistics was used to summarize the data. Binary logistic regressions were used to analyze the association between dependent and independent variables. A P-value <0.05 was considered significant.ResultsA total of 284 respondents were included in the study with a response rate of 96.6%, from which 174 (61.3%) were male and 183 (64.4%) were Oromo by ethnicity. The overall satisfaction was 79 (27.8%) (CI = 20.0–30.4). Satisfaction was high if the patients had kept their privacy (AOR = 13.332; 95% CI = 2.282–77.905) and understandability of the patient problem (AOR = 21.830; 95% CI = 0.054–77.500).ConclusionThe overall satisfaction level of the patients is low, so this demands the hospital to take further action on the identified problems to improve the services delivered to the patients.