Dietary diversity (DD) is a concern for poor people in developing countries, particularly in Africa. Most people's diets consist primarily of monotonous carbohydrate staples, with little or no animal products and few fresh fruits and vegetables. The aim of this intervention was to see how nutrition education delivered by trained health professionals improved preschool-aged children's consumption of DD and animal-sourced foods. The study used a quasi-experimental design with 588 preschool-aged children. Researchers used a multistage sample technique followed by a systematic random sampling technique. A χ2 test was used to determine the baseline differences in demographic and socioeconomic factors between the two groups, as well as the relationship between predictors and child DD and animal-source foods (ASFs). The researchers used generalized estimating equations to assess the change in the difference in outcomes between the intervention and control groups, as well as the association between predictors and child DD and ASFs. The adjusted odds ratio with the corresponding 95% confidence intervals was reported to show the strength of the association. The findings of this study revealed that there was a highly significant difference in both DD scores (DDS) and ASFs between the control and intervention groups DDS (p < 0.003) and ASF (p < 0.001). According to the findings of this study, nutrition education can significantly improve DDS and ASF consumption among preschool-aged children.