Objective This study examined the impact of overweight and obesity on health‐care expenditure among university retirees in Beijing, China. Methods Annual health surveys of retirees were conducted at Tsinghua University during 2011–2016. Individual random‐effect regressions were performed to estimate incremental health‐care expenditures attributable to overweight/obesity, adjusting for various individual characteristics. Results Compared to their normal‐weight counterparts, obesity was associated with an increase in annual out‐of‐pocket expenditure on outpatient care by 27%, inpatient care 19% and medication 15%, and an increase in annual total out‐of‐pocket health‐care expenditure by 33%. Overweight was associated with an increase in annual out‐of‐pocket expenditure on inpatient care by 13%, and an increase in annual total out‐of‐pocket health‐care expenditure by 13%. The impact of obesity on health‐care expenditure was statistically significant among men but not women. Conclusion Overweight, and obesity in particular, was associated with substantial increases in out‐of‐pocket health‐care expenditures among Chinese older adults.