OBJECTIVES: Child undernutrition is a major public health problem. Globally in 2020, 149 million children <5 y of age were estimated to be stunted (too short for age), 45 million to be wasted (too thin for height), and 38.9 million were overweight. The aim of this review was to examine previous studies to determine the factors associated with malnutrition and contribute to the existing body of evidence needed for the formulation of effective interventions. METHODS: This systematic review was conducted using the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. The Google Scholar database was used to search the studies conducted between 2012 and 2021. The included studies were searched by using some combinations of keywords and saved in Mendeley Desktop for review and referencing. RESULTS: Of 2150 articles retrieved from the Google Scholar databases, 37 met our inclusion criteria. Of the 37 studies reviewed; 13 were conducted in India, 5 in Ethiopia, 3 in Bangladesh, 2 in Ghana, 2 in Nepal, 2 in developing countries, and 1 each in Bolira, Benin, Netherland, Columbia, Pakistan, Malaysia, Africa, Egypt, Ecuadorian, and Indonesia. CONCLUSION: The most consistent factors associated with child malnutrition were maternal education, household income, maternal nutritional status, age of the child, availability of sanitation facility at home, size of family, birth order in the family, and child's birth weight. Breastfeeding and caring practices, cooking area and the fuel used, sex, and socioeconomic status of the children also contribute toward child malnutrition.