We examine the link between maternal nutrition knowledge and nutritional outcomes of children and adolescents (5–18 years) measured in terms of height-for-age Z-scores (HAZ). One particular focus is on the role of different types of nutrition knowledge. The analysis builds on household-level and individual-level data collected in urban Kenya in 2012 and 2015. Various regression models are developed and estimated. Results show that maternal nutrition knowledge – measured through an aggregate knowledge score – is positively associated with child HAZ, even after controlling for other influencing factors such as household living standard and general maternal education. However, disaggregation by type of knowledge reveals important differences. Maternal knowledge about food ingredients only has a weak positive association with child HAZ. For maternal knowledge about specific dietary recommendations, no significant association is detected. The strongest positive association with child HAZ is found for maternal knowledge about the health consequences of not following recommended dietary practices. These findings have direct relevance for nutrition and health policies, especially for designing the contents of educational campaigns and training programs.