Objective: To investigate whether preschoolers are able to identify and categorize foods, and whether their ability to classify food as healthy predicts their hypothetical food choice. Design: Structured interviews and body measurements with preschoolers, and teacher reports of classroom performance. Setting: Six Head Start centers in a large southeastern region. Participants: A total of 235 preschoolers (mean age [SD], 4.73 [0.63] years; 45.4% girls). Intervention(s): Teachers implemented a nutrition education intervention across the 2014-2015 school year in which children were taught to identify and categorize food as sometimes (ie, unhealthy) and anytime (ie, healthy). Main Outcome Measures: Preschooler responses to a hypothetical snack naming, classifying, and selection scenario. Analysis: Hierarchical regression analyses to examine predictors of child hypothetical food selection. Results: While controlling for child characteristics and cognitive functioning, preschoolers who were better at categorizing food as healthy or unhealthy were more likely to say they would choose the healthy food. Low-contrast food pairs in which food had to be classified based on multiple dimensions were outside the cognitive abilities of the preschoolers. Conclusions and Implications: Nutrition interventions may be more effective in helping children make healthy food choices if developmental limitations in preschoolers' abilities to categorize food is addressed in their curriculum. Classification of food into evaluative categories is challenging for this age group. Categorizing on multiple dimensions is difficult, and dichotomous labeling of food as good or bad is not always accurate in directing children toward making food choices. Future research could evaluate further preschoolers' developmental potential for food categorization and nutrition decision making and consider factors that influence healthy food choices at both snack and mealtime. (author abstract)