Using the 2011 and 2015 waves of the China Health and Retirement Longitudinal Study (CHARLS) linked with the 2014 CHARLS Life History Survey, we provide a comprehensive analysis on inequality of opportunity (IOp) in both body mass index (BMI) and waist circumference (WC) among middle-aged and older Chinese. We find that IOp ranges from 65.5% to 74.6% for BMI (from 82.1% to 95.5% for WC). Decomposition results show that spatial circumstances such as urban/rural residence and province of residence are dominant. Health status and nutrition conditions in childhood are the second largest contributor. Distributional decompositions further reveal that inequality in bodyweight is not simply a matter of demographic (age and gender) inequalities; our set of spatial and health and nutrition conditions in childhood become much more relevant towards the right tails of the bodyweight distribution, where the clinical risk is focused.