BackgroundProper infant and young child feeding practices have gained attention over the years as one of the interventions to reduce childhood stunting. However, there is still a gap in research to determine these relationships in children under two years and the reasons for improper feeding.ObjectiveThis study aimed to assess the relationship between feeding practices, stunting and barriers among children under two years.MethodologyUtilizing a mixed-method approach, the study involved secondary analysis of 1806 records of children aged 6–23 month, from the Next Generation Nutrition Program conducted in Tanzania (2015–2019). Both quantitative and qualitative data analyses were employed. Frequency distribution tables were utilized to describe study participants stratified by their stunting status. Subsequently, modified Poisson regression models identified predictors of stunting. Qualitative analysis encompassed deductive and inductive approaches, to extract themes that address the behaviors contributing to inappropriate feeding practices.ResultsStunting prevalence was 28.8% among children aged 6–23 months, with the majority (65%) of stunted children aged 1 year or older. Dietary diversity was low: 88.3% and 86.3% of stunted and non-stunted children, respectively, consumed less than 5 food groups. Surprisingly, early initiation of breastfeeding, time of stopping breastfeeding, and minimum dietary diversification were not significantly associated with child stunting (p-value > 0.05). Barriers to proper feeding practices identified were inadequate knowledge of feeding, maternal condition, economic hardship, cultural issues, and seasonality.ConclusionEarly breastfeeding and minimum dietary diversity were not significant predictors of stunting. However, the mother’s age and height > 150 cm reduced stunting risk while child sex, age, birth weight, marital status, and place of delivery also influenced stunting risk. It is crucial for initiatives to emphasize good feeding practices while addressing the complex factors that may hinder optimal feeding practices in this age group to reduce childhood stunting effectively.