Purpose. To develop nutrition education for preschool children based on Piaget's theory and to examine the effects of this education on children's nutritional knowledge, nutritional behaviors, and anthropometric measurements.

Design and Methods. Pre- and postexperimental design. In experimental schools nutrition education was given. Children's nutritional knowledge, food consumption frequencies, and anthropometric measurements were evaluated.

Results. The experimental group's nutritional knowledge scores increased and the group's food preferences positively changed. No significant difference was observed between the experimental and control groups' anthropometric measurements.

Practice Implications. The nutrition education program used in this study may guide nurses in preparing education for preschoolers. The participation of families is recommended in their children's nutrition program.