Background <p>Childhood growth is critical for long-term health and development. Maternal food and nutrition literacy is one of the most closely related determinants shaping children’s eating habits and growth patterns; it is a multidimensional construct comprising knowledge, attitudes, and behaviors. There are limited studies in Türkiye investigating the relationship between maternal food and nutrition literacy and child and adolescent growth across a wide age range. This study aims to assess the relationship between maternal levels of food and nutrition literacy and their children’s anthropometric growth indicators.</p> Methods <p>This descriptive cross-sectional study was conducted with mothers living in Türkiye who had at least one child aged 2–19 years (<i>n</i> = 263). The height and weight measurements of mothers and children were recorded based on self-reports; Weight-for-Height (WHZ), Height-for-Age (HAZ), BMI-for-Age (BAZ), and Weight-for-Age (WAZ) z-scores were calculated using World Health Organization references for the children’s growth assessment. Mothers’ food and nutrition literacy was measured using the Food and Nutrition Literacy (FNL) Scale, and FNL scores were divided into tertiles (T1, T2 and T3). Nutritional practices and growth indicators were compared between the three groups using appropriate statistical tests. In addition, multivariate linear regression models were created to examine the relationships between growth indicators and FNL and its subscales.</p> Results <p>The mean age of mothers was 38.10 ± 8.17 years, and a significant number of the mothers had limited knowledge (39.92%), attitudes (47.15%), and behaviors (51.33%). Mothers with high FNL levels were more likely to start complementary feeding after 6 months, pay attention to label information, and monitor their children’s food consumption more frequently (<i>p</i> &lt; 0.05). However, no significant difference was observed in the children’s WHZ, HAZ, BAZ, and WAZ values among the three FNL groups (<i>p</i> &gt; 0.05). According to multivariate regression analysis, the behavioral subscale of maternal food and nutrition literacy was positively and significantly associated with HAZ in children and adolescents aged 5–19 years after adjustment for maternal BMI and feeding practices (β = 0.158, <i>p</i> &lt; 0.05 in Model 2; β = 0.177, <i>p</i> &lt; 0.05 in Model 3). No significant relationship was found between the knowledge and attitude subscales and growth indicators.</p> Conclusions <p>This study demonstrates that maternal food and nutrition literacy, particularly its behavioral component, is associated with HAZ, a measure of long-term growth in children and adolescents. The limited effect of the knowledge and attitude subscales alone on growth highlights that the behavioral translation of nutrition literacy is critical for child health. The findings suggest that family-based and behavior-focused educational interventions may be more effective than those focused solely on knowledge transfer. Future studies with longitudinal designs and incorporating additional variables such as the nutrition environment, diet quality, and physical activity will provide a more comprehensive explanation of the effects of maternal food and nutrition literacy on growth.</p>