Under the background of global warming, Guangdong Province has been frequently affected by disastrous weather events including persistent low temperature and rain, drought, torrential rain, and typhoons. Such extreme weather severely affects the yield and quality of Shatian pomelo and other crops, restricting the sustainable development and economic benefit improvement of the Shatian pomelo industry in Guangdong. As an innovative type of agricultural insurance, weather index insurance conducts disaster verification and loss determination based on objective data, with convenient claim settlement. It can effectively disperse and transfer meteorological disaster risks in agricultural production. To avoid or mitigate the adverse impacts of disastrous weather on the yield and quality of Shatian pomelo, and to promote the expansion, diversification, and upgrading of agricultural weather index insurance, it is urgent to carry out the design and application of weather index insurance products for the Shatian pomelo industry in Guangdong. Taking Meizhou City as a case, this research screens key meteorological indices at different growth stages and constructs a meteorological index-disaster damage model for Shatian pomelo based on daily meteorological data and Shatian pomelo yield data from 2005 to 2023. The Anderson-Darling (A-D) test is employed to select the optimal probability distribution model for the sequence of Shatian pomelo meteorological indices, determine the insurance payout ratio, and obtain pure premium rates and corresponding premiums for different levels of yield reduction rates. By substituting historical meteorological data, the insurance payout rates for the recent 10 years, 20 years, and 30 years are calculated to verify their compliance with market requirements. The results indicate: (1) The low-temperature index during the bud differentiation stage and the sunshine index during the flowering stage in Meixian District and Dabu County are key meteorological indices leading to Shatian pomelo yield reduction, which are designed as the claim indices for the insurance. (2) When the low-temperature index during the bud differentiation stage in Meixian District reaches 11 days, the sunshine index during the flowering stage in Meixian District reaches 8 days, the low-temperature index during the bud differentiation stage in Dabu County reaches 12 days, and the sunshine index during the flowering stage in Dabu County reaches 8 days, the meteorological index insurance for Shatian pomelo is triggered. The pure premium rates corresponding to different levels of yield reduction rates range from 1.04% to 6.93%, 0.79% to 4.58%, 3.25% to 8.29%, and 1.88% to 5.43%, respectively, with the premiums per hectare of Shatian pomelo planting area ranging from CNY 470 to 3,120, CNY 357 to 2,060, CNY 1,462 to 3,731, and CNY 846 to 2,444, respectively. (3) Through verification of historical insurance claims, the average insurance payout rates in Meizhou City for the recent 10 years, 20 years, and 30 years are 65.86%, 69.40%, and 74.61%, respectively. The designed Shatian pomelo meteorological index insurance meets the market requirements for insurance payout rates and can provide a reference for the new round of policy-based agricultural insurance.