Background: Breast feeding will have the intended outcome when it is initiated timely and exclusive for the first six months. Introducing prelacteal feeding and inadequate amount of breast milk contributes to over a million avoidable infant deaths each year in developing countries. The purpose of this study was to assess prelacteal feeding practice and associated factors among mothers attending immunization clinic in Harari region government health institutions. Methods: An institutional based cross-sectional study design was conducted among 634 mothers and infants dyads attending ten public health facilities. Systematic random sampling method was used to select the study participants. An exit interview using pretested structured questionnaire was conducted about their experience on prelacteal feeding and related experience. Logistic regressions with OR and 95% confidence interval were computed. Result: Two hundred seventy eight (45.4%) of mothers gave prelacteal liquids for their infants. The common pre-lacteal food includes sugar or glucose water 121 (43.5%) followed by milk other than breast milk 70 (25.1%). Home delivery, failure to attend ANC, late breastfeeding initiation and influence by friends were significantly associated with prelacteal feeding. Conclusion: The prevalence of prelacteal feeding was relatively high in the area. Failure to attend ANC, giving birth at home, late initiation of breast feeding and influence of friends and relatives to give prelacteal feeds for their new born infants were found to be positively associated with prelacteal feeding.