The objective of the study is to investigate the effect of service quality on customer satisfaction at Ethiopian Electric Utility (EEU) Jimma District. To meet the objective, Data for this study was collected from 627 respondents through the survey from Ethiopian Electric utility customers of four purposely selected towns, these include Jimma, Agaro, Sokoru and Limmu Genet towns. In addition to survey questionnaire, semi structured interview and different types of secondary data were utilized. .SERVQUAL model with seven dimensions were used to measure service quality of the company. Accordingly, Tangibility, Reliability, Empathy, Security and stability measures were found to significantly determine customer satisfaction but Responsiveness and Assurance were not found to be significantly affecting customer satisfaction. Finally, by identifying the strengths and weaknesses pertaining to the dimensions of service quality, EEU should better allocate resources to provide better service and ultimately bring better satisfaction to its customers. Moreover, since customers’ expectations change over time, it is necessary to contact customers regularly and assess their service experiences.