Background: The importance of assessing "food literacy" since youth has been highlighted and, to this purpose, valid and consistent instruments are needed. This study aimed to assess the validity and internal consistency of the preschool-FLAT (Food Literacy Assessment Tool). Methods. 505 children from 21 kindergartens, recruited within the Training-to-Health Project in Palermo (Italy), underwent oral sessions and activities on food-related aspects. Their knowledge/skills were recorded in the preschool-FLAT. The following scale measures were assessed: Content validity; internal consistency (Chronbach's alpha coefficients); construct validity (Structural Equation Modeling-SEM); discriminant validity (intervention subgroup of 100 children vs. control group of 27 children). Results. Acceptable content validity of a 16-items scale and overall adequate internal consistency were revealed: Content validity index (CVI) 0.94, content validity ratio (CVR) 0.88, Chronbach's alpha 0.76. The SEM revealed a 4-factor model fitting the data well (comparative fit index 0.939, root mean square error of approximation 0.033). Discriminant validity was good (intervention group scoring higher than control, p < 0.001, unpaired Student's t-test). Conclusion. The preschool-FLAT revealed good psychometric properties, adequate validity and internal consistency. This is the only instrument in the literature specifically targeted to 3-6 years old children that could be effectively used to assess food literacy.