This paper analyzes the effect of meal regularity on adult obesity. For solving a potential endogeneity problem, a propensity score matching method is applied. BMI, waist and daily energy intake are selected as outcome variables. We set the two hypotheses on the relationship between obesity and eating regular meals or eating breakfast regularly. Analytical results show that the adults who are having regular meals intake more calories than those eating irregular meals, but his or her BMI is lower than those eating irregular meals. And the adults eating regular breakfast are proven to intake more calories than those eating irregular breakfast, but his or her BMI is lower than those eating breakfast irregularly. These results suggest that regular eating is effective in reducing obesity.