BACKGROUND: Malnutrition is a public health concern in Ethiopia. This might be correlated with inappropriate infant and young child feeding practice. This in turn is affected by Mothers' knowledge on feeding practice. However, information on mothers' knowledge on infant and young child feeding recommendation was scarce in Ethiopia. Therefore, this study was designed to assess mothers' knowledge on infant and young child feeding recommendation and associated factors in slum areas of Bahir Dar City, Ethiopia. METHODS: A community based cross-sectional study was conducted from May 1-26/2015. Systematic sampling technique was used to select respondents. Data were collected by pretested, structured, interviewer administered questionnaire. Data were entered and analyzed by SPSS version 20 software. Knowledge score was computed. Binary and multivariable logistic regression analysis were used to identify factors associated with maternal knowledge. RESULTS: Only 28.7% of mothers had sufficient knowledge on infant and young child feeding recommendation. Factors associated with mothers, knowledge were above primary education [AOR 2.5, 95% CI (1.5, 3.9)], possession of radio [AOR 1.7, 95% CI (1.1, 2.7)], attending antenatal care [AOR 2.4, 95% CI (1.5, 4.0)], and having employed husband [AOR 2.3, 95% CI (1.2, 4.4)]. CONCLUSION: Mothers' knowledge on infant and young child feeding recommendation was very low. Hence, education on infant and young child feeding recommendation should be strengthened during antenatal care visit and using mass media especially for mothers with lower educational status to fill up of this gap.