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By integrating hail data collected from hail prevention sites, meteorological stations, and the China Meteorological Administration’s meteorological disaster management system, the spatiotemporal distribution characteristics of hail in Yunnan from 2012 to 2023 are statistically analysed, and the differences between them and the observation results of meteorological stations are explored to provide a basis for hail monitoring, forecasting, and scientific hail suppression. The results show that the annual average number of hail days and county days in Yunnan is 100.5 days and 324.0, with significant interannual differences and an increasing trend, with a yearly increase of 1.1 days and 6.3 county days. The seasonal characteristics of the two are prominent, with the highest values in summer, followed by spring, and significantly reduced in autumn and winter. The corresponding values are 46, 34.1, 10.8, and 9.6 days and 166.2, 110.4, 16.3, and 31.1 county days, respectively. The monthly variation can be classified into four types. The predominant pattern is dual-peak, with a primary peak in July-August and a secondary peak in March-April. The second pattern is single-peak in July-August for hail days but in March-April for hail county days, and the other patterns are single-peak in March-April for hail days but in July-August for hail county days, and both multi-peak. On average over the years, both exhibit a typical dual-peak pattern with a primary peak in July-August and a secondary peak in March-April. The daily variation of hail shows a single-peak pattern at 16:00, with hail concentrating between 13:00 and 19:00, particularly in summer and autumn. The horizontal spatial distribution of hail days is categorised into four types: scattered hail type, two band-shaped hail type, multiple hail type to the east and north of central Yunnan, and multiple hail type in southern and western Yunnan. On average over the years, the maximum number of hail days is from Qujing to Zhaotong (up to 11.8 days in Xuanwei), followed by the area from Yuxi to northern Honghe, then from Dali to Lijiang, and in Baoshan. However, there are significant differences in the seasonal and monthly horizontal distribution, with hail occurring in the western and southern regions during winter and spring, developing eastward from late spring to early summer, expanding towards the central region in summer, and retreating towards the west and south in autumn. On the vertical distribution, the number of hail days increases first and then decreases with altitude, with the most hails occurring at altitudes of 1.5-2.0 km. The number of hail days at low altitudes (0.0-1.0 km) is a single-peak pattern in April, a dual-peak pattern in April and July at mid-altitudes (1.0-2.0 km), and a single-peak pattern during July-August at high altitudes (≥2.0 km). At mid- and low altitudes, hail mainly occurs in spring, followed by summer, and least in autumn, and at mid- and high altitudes, hail mainly occurs in summer, followed by spring, and least in winter.