Background: Maternal mortality and morbidity are attributed to poor maternity quality of care.rnGlobally, more than half a million women die annually as a result of complications of pregnancyrnand childbirth.So, at a time when global efforts to reduce maternal mortality have been steppedrnup, it is important to look at maternal satisfaction and factor affecting it.rnObjective: The objective of the study was to assess the mothers’ satisfaction with deliveryrnservices at health institutions and associated factors in West Arsi Zone, Oromia Region,rnEthiopia, 2016.rnMethods: A facility based cross-sectional survey with exit interview was conducted in WestrnArsi, Oromia Regional State, Ethiopia.Four hundred seventy seven (477) postpartum mothersrnwereenrolled in the study. Data was checked, coded and entered to Epi-data and was exported tornSPSS version 21 for analysis. Multivariate and binary logistic regression was applied to identifyrnthe relative effect of each explanatory variable on the outcome (satisfaction).rnResults:This study finding showed that the overall satisfaction level of mothers with deliveryrnservice was 74.6%. Women who had no formal education, primary education and secondaryrneducation were less satisfied than women who had diploma and above (AOR= 0.851, 95%CI:rn0.306, 0.863, AOR=0.399, 95%CI: 0.154, 0.730and AOR=0.569, 95%CI: 0.229, 0.412)rnrespectively. Women who had monthly income less than 650ETB were three times morernsatisfied with delivery service than women who had monthly income more than 1900ETBrn(AOR=3.294,95% CI:1.337,8.114).Mothers who had assisted vaginal delivery were less satisfiedrnthan mothers who had caesarian section (AOR=0.31, 95%CI: 1.253, 4.115).Mothers those theirrnprivacy measures was maintained were six times more satisfied with their delivery service atrnhealth institution than those did not maintained(AOR=6.988, 95%CI:4.047,12.066).rnConclusion: Only 74.6% of the mothers were satisfied from the overall level of delivery service.rnFrom this study, educational status, economical status, privacy of mothers, mode of delivery andrnwaiting time were important predictors of level of satisfaction.rnRecommendation: Health institutions and health personnel should work on identified factors tornincrease mother’s satisfaction with delivery service.Future studies should consider gatheringrnmore data from a more diverse sample to address the generalizability issue.rnKeywords: Mothers’ satisfaction; Delivery service; Health institution; West Arsi zone; Ethiopia