This study was carried out to compare the nutrition knowledge, nutrition attitudes and eating behaviors of dietitians and non-dietitians. The subjects of this study were 148 dietitians and 195 non-dietitians who are working in the metropolitan area. The general characteristics, nutrition knowledge, nutrition attitudes and eating behaviors of the subjects were surveyed using a self-administered questionnaire. The results were as follows: The result of anthropometric data and body mass index showed no significant differences between dietitians and non-dietitians groups. The dietitian group ($16.61{pm}1.82$) showed a significant difference (p < 0.001) compared to the non-dietitian group ($14.60{pm}2.17$) in nutrition knowledge scores. Nutrition attitudes of the dietitian group ($36.66{pm}6.91$) was a little higher than the non-dietitian group ($36.21{pm}7.95$), but not a significant difference. The dietitian group ($61.52{pm}9.37$) and the non-dietitian group ($62.50{pm}11.25$) were no significant difference in eating behaviors. The correlation between nutrition knowledge scores and nutrition attitudes score of dietitians and non-dietitians groups were no significantly difference and also the correlation between nutrition knowledge scores and eating behaviors scores were not statistically significance. Whereas, the correlation between nutrition attitudes and eating behaviors showed a significant difference (dietitian r = 0.40829, non-dietitian r = 0.51914). From these results, we could see the necessity of emphasis of nutrition knowledge by mending the education is necessary to enable dietitians to apply that in real life. Also it is important to guide non-dietitians to adjust their nutrition knowledge, nutrition attitudes and eating behaviors.