This study was conducted in order to investigate the effect of diet therapy on over weight and obese humans in Korea Subseng Research Institute from January 1, 1994 to August 31, 1997. The constitutions of subjects were classified mild negative, strong negative, mild positive and strong positive respectively by ecology and O-ring test. These results were obtained from the subjects who practiced at least 75% diet therapy recommended for over weight and obese human for 14~400days. The constitutions of over weight and obese human by Relative Body Weight (RBW$geq$110%) were 89 mild negative humans, 62 strong negative humans, 56 mild positive humans and 30 strong positive humans. The constitutions of over weight and obese human by Body Mass Index(BMI$geq$25) were 77 mild negative humans, 50 strong negative humans 46 mild positive humans and 23 strong positive humans. The negative subjects were higher than the positive subjects on over weight and obese humans. The diet therapy related to constitiution on over weight and obese humans showed RBW reduction of 6.73$pm$0.53 on mild negative human, 7.78$pm$1.69 on strong negative human, 6.94$pm$0.76 on mild positive human, and 7.80$pm$1.15 on strong positive human at p<0.001 by student paired t-test. The diet therapy related to constitution on over weight and obese humans showed BMI reduction of 1.47$pm$0.12 on mild negative humans, 1.24$pm$0.11 on strong negative humans, 1.59$pm$0.17 on mild positive humans, and 1.66$pm$0.30 on strong positive humans at p<0.001 by student paired t-test