This research aimed to 1) study the result of using token economy and social reinforcement toward behavior of eating vegetables and fruits of experimentation group of preschool children and 2) compare behavior of eating vegetables and fruits of preschool children between before and after experimentation. Target group for this research was five students at age 4-5 years, studying in kindergarten level 2 at Khon Kaen Vithes Suksa School, during the first semester of 2010 academic year. They had also eaten vegetables and fruits less than one-quarter (25%) of the quantity they were determined to eat. Instruments for collecting data consisted of parent questionnaire, reinforcer survey form, evaluation form for eating vegetables and fruits, score record form for eating vegetables and fruits and record form for rewards redemption. Data was analyzed through statistic of the Wilcoxon Signed Rank Test. Research findings were found as follows: 1) Behavior of eating vegetables and fruits of experimental group of students reinforced by token economy and social reinforcement was increasingly found. 2) After experimentation, this group of students could have higher scores of eating vegetables and fruits with statistical significance level at ".05".
