AIM: To explore the spatiotemporal distribution and the association with environmental factors of age-related cataract in Yushu, Qinghai Province from January 2023 to March 2025.METHODS:A total of 1 121 patients with age-related cataract admitted to our hospital from January 2023 to March 2025 were collected, 121 patients were excluded according to the exclusion criteria, and finally 1 000 patients living in Yushu Tibetan Autonomous Prefecture, Qinghai Province were included, with an average age of 71.45±8.25 years. ArcGIS10.2 was used to draw the spatiotemporal distribution map of age-related cataract in each county of Yushu, Qinghai Province, and OpenGeoda was used for global spatial autocorrelation analysis. Binary Logistic regression was used to analyze the correlation between environmental factors and the incidence of age-related cataract. Multivariate Logistic regression was used to analyze the influencing factors of age-related cataract. LCA(Mplus 7.4 software)was used to compare the differences in factor distribution characteristics.RESULTS:There were 438 cases in 2023, 472 cases in 2024, and 90 cases in 2025 among the 1 000 cases of age-related cataract. The spatiotemporal distribution map of age-related cataract in each county of Yushu, Qinghai Province showed that the incidence rate was the highest in Qumalai County and Zhiduo County, followed by Chengduo County and Yushu City, and the lowest in Nangqian County and Zaduo County. The spatial distribution presented a incidence feature of high in the northwest and low in the southeast. The highest number of confirmed cases was from July to September 2023 and 2024, accounting for 31.90% of the study population, which might be related to the peak of ultraviolet radiation intensity in the summer on the plateau. The global autocorrelation Moran's I coefficient showed that the spatial distribution characteristics of age-related cataract at the county level presented a bimodal distribution, with all Moran's I coefficients being positive. The incidence of age-related cataract in each year had a spatial positive correlation(P<0.05). The peaks were in July to September 2023 and 2024, with values of 0.423 and 0.451, respectively. The annual average ultraviolet radiation, altitude, and annual average PM2.5 concentration positively correlated with age-related cataract(all P<0.05), while the annual average temperature and annual precipitation negatively correlated with age-related cataract. However, only the annual average temperature significantly correlated with age-related cataract(P<0.05). After adjusting for confounding factors, the correlations remained stable(P<0.05). Multivariate Logistic regression analysis showed that the annual average ultraviolet radiation, altitude, annual average temperature, and annual average PM2.5 concentration were independent influencing factors for age-related cataract(all P<0.05). LCA showed that the effects of annual average ultraviolet radiation, altitude, annual average temperature, and annual average PM2.5 concentration on age-related cataract were heterogeneous.CONCLUSION:From January 2023 to March 2025, there were obvious spatiotemporal characteristics and distribution patterns of age-related cataract in Yushu, Qinghai Province. Temporally, the number of confirmed cases reached the peak in July to September each year. Spatially, the incidence rates in each county were significantly different, presenting a distribution feature of high in the northwest and low in the southeast. In addition, ultraviolet radiation, altitude, temperature, and PM2.5 concentration are important environmental factors affecting the incidence of age-related cataract in Yushu, Qinghai Province.