【Objective】The spatiotemporal variation characteristics and driving factors of fertility quality of paddy soils in China were studied. 【Method】 Based on the long-term monitoring data (1988-2017) of the Ministry of Agriculture and Rural Affairs in the main rice areas in China, the fertility quality of paddy soil in the main rice areas was evaluated by the fuzzy mathematics (Fuzzy) method, and combined geo-statistics with machine learning.【Result】In the recent 30 years, the soil fertility index (SFI) of the rice area in China increased significantly (P < 0.05). From the prophase (1988-1999) to the interim (2000-2009) and from the interim to the recent (2010-2017), the national paddy field SFI increased by 6.9% and 17.7% on average, respectively. The characteristics of SFI varied in different time stages in the main rice regions. The rice regions in southwest China and the middle reaches of the Yangtze River showed a significant increasing trend of slow in the early period (from prophase to interim) and fast in the later period (from interim to recent) (P < 0.05). Also the rice fields in South China and the Yangtze River Delta showed a rising trend of fast in the early stage (from prophase to interim) and stable in the later stage (from interim to recent). There was a decreasing trend in the earlier period (from interim to recent) and increasing in the later period (from interim to recent) in the Northeast rice region. At the recent, the distribution of paddy SFI in China showed a trend of higher in the north and lower in the south, higher in the east and lower in the west. The area with SFI exceeding the national average (0.61) accounted for 50.2%. Compared with the SFI of the rice region in the interim, the SFI showed an overall upward trend in the recent. The increased area accounted for 69.3%. The relative importance of soil organic matter and total nitrogen to SFI change (19.4%-60.3%) was much higher than that of other indexes (0.1%-13.3%) in all rice areas in the prophase and interim (except the middle stage of the northeast rice region). The relative importance of soil Olsen-P, available potassium and soil pH (except the northeast rice region) increased in all rice regions, and the relative importance of soil Olsen-P content increased to the maximum in the middle reaches of the Yangtze River. However, the relative importance of soil total nitrogen and soil organic matter content was greater in all rice regions.【Conclusion】In conclusion, the spatiotemporal variation characteristics of soil fertility quality and the changes of key driving factors at different stages and in different rice regions should be comprehensively considered. The balanced fertilization measures should be optimized to prevent and control soil acidification and to improve the fertility quality of paddy soil.