To investigate the comparison of dietary status and health behaviors according to obesity, 239 male workers were selected and classified as normal (18.5-22.9 27.2%), overweight (23-24.9, 37.7%), and obese (25-29.9, 35.2%) by body mass index (kg/m2). The SAS (ver. 9.2) program was used and verified by the chi-square and f-value methods. Drinking frequency(2-3 times a week) was higher in normal males(45.3%), but not as high as in obese males (48.1%) (p<0.001). Smoking frequency and amount were the highest in overweight males, but not-quit-smoking was high in obese males(51.9%) (p<0.001). Exercise time was longer in normal males(108 minutes) than other groups(69 overweight males, and 82 obese males (p<0.01). Obese groups(73.8%) slept well (p<0.001), but overweight males(44.4%) showed less than 6 hours of sleep (p<0.01). Meal frequency differed by group(two meals a day 67.7% in normal males (p<0.001), no-snack 65.5% in obese males(p<0.001). The frequency of eating-out was once a day in normal males (38.5%), differed in the eating-out time (lunch(45.8%) in normal males, dinner in overweight males(52.1%) and obese males(59.5%) (p<0.01). Korean food (49.3%) was selected, but noodle differed by group(10.2% normal 21.5% obese (p<0.01). Self-perception of body differed from the body's actual condition(p<0.001). For weight control, exercise(56.4%) was practiced more than diet(18.6%). Nutrition knowledge was poor (correct answer rate was 36.7% in normal males, 41.7% in overweight males, and 46.7% in obese males). For eating attitudes, obese males answered more in "flexible to change eating habits", "supplemented when poor eating"(p<0.001), normal responded in "impact on nutrition to health", "try new food for health"(p<0.01). From these results, it is evident that male workers, especially overweight ones, must work to learn more about health and nutrition so as to combat chronic diseases.