For evaluating the accuracy of monthly IMERG (V06) precipitation products in Guangxi, utilizing monthly precipitation from 91 observation stations from 2001 to 2020 as reference, employed three quantitative indicators - Correlation Coefficient (CC), Root Mean Square Error (RMSE), and Relative Error (RE), and divided Guangxi into three zones: arid zone (mean annual precipitation <1300mm, Zone I), moderate precipitation zone (mean annual precipitation 1300-1700mm, Zone II), and rainy zone (mean annual precipitation >1700mm, Zone III), analyzed the accuracy characteristics of IMERG products from the perspectives of spatial, temporal, and changing trends. The results showed that: 1) Overall, IMERG products show strong correlation but high dispersion with observed data, the accuracy of Final product is better than Early and Late product, and the accuracy of Early and Late product is similar; Final product overestimate monthly precipitation, while Early and Late product underestimate monthly precipitation. 2) In terms of spatial distribution, the CC and RMSE of all series products are highest in Zone III, greater correlation and higher dispersion occur in areas with more precipitation; Precipitation is overestimated in Zones I and II, and underestimated in Zone III, the Final product has a higher overestimation in Zones I and II compared to Early and Late product, while the underestimation is lower in Zone III. 3) In terms of temporal, Early and Late product have lower correlation in January, February, April, May, June, and December, with higher dispersion from April to September, rainy season (April-September) show greater correlation and higher dispersion compared to dry season (October to the following March), overestimation of precipitation occurs in March-May, while underestimation occurs in September-November; Final product have lower correlation and higher dispersion in April to September, accuracy in rainy season is lower than dry season, precipitation is overestimated in zones I and II in all months; in Zone III, precipitation is only overestimated in January and October, while the rest are underestimated; IMERG products have higher accuracy in dry years. 4) In terms of accuracy variation, a decreasing trend appear in the 0-300mm precipitation range, with the estimation error shifting from overestimation to underestimation; As the years increase, accuracy shows a decreasing trend, with the estimation error tends to be overestimated. Monthly IMERG products show high accuracy in Guangxi, but there are significant differences in different periods and regions, evaluation is necessary for specific time and area during application.