The Global Burden of Disease Study 2021 (GBD 2021) analyzed 371 diseases and injuries using 100,983 data sources, estimating years lived with disability, years of life lost, disability-adjusted life years, and healthy life expectancy. From 1990 to 2019, the annual rate of change in global all-cause mortality ranged from -0.9% to 2.4%, while deaths increased by 10.8% and 7.5% in 2020 and 2021 respectively due to COVID-19. In 2021, COVID-19 was the second lea-ding cause of death globally, with a mortality rate of 94.0 per 100 000. The mortality rates of other major causes, such as ischemic heart disease and stroke were 108.7 and 87.4 per 100 000, respectively. Global life expectancy rose from 65.5 years in 1990 to 73.3 years in 2019 but dropped to 71.7 years in 2021 due to COVID-19, which reduced life expectancy by 2.2 years, significantly impacting the trend of health improvement. In China, GBD 2021 data shows a significant increase in life expectancy from 1990 to 2021: from 69.9 to 80.7 years for women and from 65.7 to 74.9 years for men. However, non-communicable diseases such as cardiovascular diseases, cancers, and chronic respiratory diseases remain major health threats. In 2021, these diseases had the highest burden among the top ten causes in China, with rising incidence and morta-lity rates. Major health risk factors in China include tobacco, hypertension, and dietary risks. This paper, through the systematic analysis of GBD 2021 data, reveals current trends in disease burden globally and in China, and proposes public health strategy recommendations. China should enhance chronic disease management, improve public health emergency responses, address health inequalities, and promote basic research and international cooperation to improve overall health levels.