Abstract: Objective: To systematically quantify the spatiotemporal evolution characteristics of the disease burden attributable to overweight and obesity among adults in China and globally from 1990 to 2021, to meticulously analyze the independent contributions of age-period-cohort effects, and to project the development trajectory of this disease burden from 2022 to 2050. Methods: Data for Chinese and global adults from 1990 to 2021 were extracted from the Global Burden of Disease (GBD) study database. Age-standardized mortality rates (ASMR) and age-standardized disability-adjusted life years rates (ASDR) were utilized as key assessment indicators. The Estimated Annual Percentage Change (EAPC) model was employed to quantify the overall temporal trends in disease burden. A Bayesian Age-Period-Cohort (BAPC) model was used to meticulously analyze the independent impacts of age, period, and birth cohort on the disease burden, and to forecast trends from 2022 to 2050. Results: From 1990 to 2021, both the ASMR (EAPC=1.25%) and ASDR (EAPC=1.71%) attributable to overweight and obesity in China exhibited an upward trend, with growth rates significantly exceeding global averages (0.17% and 0.66%, respectively). The increase in burden was more pronounced among males (ASMR-EAPC=1.69%, ASDR-EAPC=2.07%) compared to females (0.85% and 1.36%, respectively). The related burden generally increased across all age groups in China, with a significant rise observed in young and middle-aged adults. Unlike the global pattern, the burden in the elderly population in China did not show signs of alleviation. BAPC model projections indicate that by 2050, the ASMR and ASDR in China will continue their rapid growth trajectory. The overall ASDR (4 248.74 per 100 000 person-years) is projected to surpass the global level (3 413.90 per 100 000 person-years), and the male ASMR (77.34 per 100 000 persons) is expected to exceed the projected global male figure for the same period (73.18 per 100 000 persons). Conclusions: The disease burden attributable to overweight and obesity in China demonstrated a rapid growth pattern between 1990 and 2021. The future burden presents considerable severity and complexity, with the male population facing particularly prominent risks.