Background: For optimal nutritional status, health, and growth of the children the knowledge, attitude, and practice (KAP) of mothers/caregivers on infant and young child feeding are key factors. Hence, in this study, the knowledge, attitude, and practice of the mothers/caregivers on infant and young child feeding were assessed. Methods: A cross-sectional study was carried out among 486 mothers/caregivers from Assosa Districts in Assosa Zone of Benshangul Gumuz Region, Western Ethiopia, semi-structured interviewer-administered questionnaire was used. To isolate independent predictors for good knowledge, good practice, and favorable attitude of the mothers/caregivers related to child feeding, multivariable logistic regression analyses were performed. Results: Out of 486 study participants, only 19 % of the participants knew the importance of colostrum’s, 83.1% of respondents know the exact time of complementary feeding initiation. Furthermore, the Majority, (84%) of respondents believed that breast milk was the first feed that should be consumed by the child within 1hour of birth.In bivariate analysis, the data showed that there was no association between mothers’ knowledge and the variables analyzed; these variables include a place of the respondent, sex, marital status, religion, occupation, family size, etc. In the binary logistic regression analysis age of mothers, educational status of the mother, place of delivery, father educational status, father involvement & support, information about IYCF, discuss with your husband about IYCF and ANC follow up were statistically associated with mothers knowledge on IYCF recommendation.Conclusions: Overall mothers had good knowledge and a fair attitude about IYCF practices. Age of mothers, Place of delivery, information about IYCF, and ANC follow-up were statistically associated with mother's knowledge of IYCF. To support IYCF practices, behavior change communications intervention strategies should be introduced in mothers to bridge the gap between knowledge and practices.