Background: Colostrum is yellow to orange color, thick and sticky first milk produced by the mammary glands which was universally recommend to feeding for every newborn. It has Laxative effect and contains bioactive immune factors which protect a neonate against a variety of infections and allergic diseases. Globally, around 5.6 million children died before reaching their fifth birthday, of those, 2.6 million (46%) died in the first 30 days of life. Approximately 7000 newborns died every day, most of which occurred within first 7 days after birth, with about 1 million dying on the first day and close to 1 million dying within the next 6 days in 2016. Various factors can effectively reduce neonatal mortality to greater levels early initiation of Colostrum feeding and exclusive breastfeeding for the first 6 months of life is one of them which prevent around 20% newborn deaths and 13% under-five deaths. Even those few studies conducted on Colostrum feeding in Ethiopia there is no sufficient information in our study area. There for this study will try to fill the information gaps and serve as implementation guide and reference for stake holder and other researchers. Objective: To assess knowledge, attitude and practices of colostrum feeding among postnatal mothers in Harar Town governmental Hospital Harar, Eastern Ethiopia 2019. Methods and material: Health facility based cross sectional study was condcted on 306 women attending delivery service in Harar Town Jugal and Hiwot Fana Specialized university Hospitals. Sample was allocated proportionately and study participant was selected by systematic random sampling. Collected and checked data were entered in to Epi Data software version 3.02 and exported and analyzed using SPSS version 21. Mean value were used to classify as good or Poor knowledge, altitude and practice on hand hygiene. Finding was summarized and presented in different forms of diagrams and tables and statement. Result: The overall prevalence of good knowledge, altitude and practice on this study was 96 %, 89 % and 70 % respectively. Majority 65.5 % and 94 % of the mother replied that important for growth and development of baby and it protect disease from their new born. Few 8% provide other than colostrum after birth due to different reasons. Conclusion and Recommendation: Even if the overall prevalence of good knowledge. Altitude and practice was higher on this study few clients does not now initiation time of breast and also provide other substance instead of colostrum and discard it due to fear of abdominal cramp and their believed that it was not clear. Therefore responsible bodies and stake holders need to work for alleviating such misconception and information gaps.