This paper aims to examine the factors determining adult overweight or obesity in rapidly developing urban China. Quantitative analysis was performed using individual questionnaire data from the Survey for the Purpose of an Estimation of Preference Parameters conducted by Osaka University in six urban cities, Beijing, Shanghai, Guangzhou, Chengdu, Wuhan, and Shenyang. The estimation results of relative-risk ratios by the multinomial logistic regression model showed that 1) women and those whose subjective satisfaction with health were poor tended to be lean; 2) men, middle-aged or elderly people, those eating meals at irregular times, and those with a lower relative standard of living compared to others living around them tended to be overweight; and 3) men, middle-aged or elderly people, those with a strong sense of stress and depression, those with a lower level of subjective satisfaction with daily life, and those with lower or higher annual household incomes tended to be obese. However, the frequency of physical exercise and education level, which were pointed out by previous studies to be determinant factors of overweight and obesity, are not significant. It is recommended that various preventive measures targeting high-risk groups be introduced and promoted.