PURPOSE: To compare and analyze the effects of aerobic exercise, intermittent diet, aerobic exercise and intermittent diet on food intake and weight in rats. METHODS: 26 male SD rats aged 6 weeks were randomly divided into control group (Con, 6 rats), exercise group (Ex, 7), diet group (D, 6), exercise & diet group (ExD, 7) and fed with normal diet. Exercise program: running on the treadmill for 1h on Monday, Tuesday, Thursday and Friday. Intermittent diet: diet for two days a week, Wednesday and Saturday. Record the food intake and weight every day. Statistic Analysis: one-way ANOVA is performed on the average daily food intake (DFI), average weekly food intake (WFI) and average weekly body weight (BW) of the 4 groups. RESULTS: WFI of each group fluctuated within 8 weeks, and it presented Con > Ex > D > ExD. Con-Ex' p>.05. p : Significant difference between groups. Con-D, Ex-D, Con-ExD, Ex-ExD, and D-ExD' p<.05. On the non-diet day, DFI presented D > ExD > Con > Ex. Con-Ex' p>.05, but Con-D, Con-ExD, Ex-ExD, and D-ExD' p<.05. BW appeared Con > Ex > D > ExD from the end of the first week. At the end of the experiment, Con-Ex and Ex-D' p>.05, but Con-D, Con-ExD, Ex-ExD and D-ExD' p<.05. The difference of BW was dynamic. The weight loss effects of D and ExD appear early, starting at week 1. CONCLUSION: D and ExD had significant effects on reducing WFI, but Ex can not. After dieting, the food intake will be significantly improved, and ExD consumed significantly less food than D. D and ExD had a significant effect on weight loss, but Ex can not.