Food security is one of the largest concerns in the country, but in reality, it often presents an abnormal phenomenon of “abundant grain production with the poor economy”. Considering that the existing research on resource curse has hardly touched upon the topic of farmland and grain resources curse, and there is a lack of quantitative empirical analysis on the impact of farmland and grain resources abundance on regional economic development, this study uses an organic combination of provincial and county scales to analyze the spatial differences of the curse in China’s provinces and counties, carry out empirical testing of China’s farmland–grain resource curse based on panel data collected from 31 provinces in 2001–2021 and 2843 counties in 2014–2021, and revealed its influence mechanism by using the econometric model. The results suggest the following: (1) the curse of farmland and grain resources occurs to different degrees in more than 77 % of provinces and about 63 % of counties in China, and about 19 % of counties are at the serious and extremely serious levels. (2) The curse of farmland and grain resources occurs in regions with high grain output, and has a negative influence on regional economic growth. In terms of estimation results at the provincial level, for every 1 % increase in total cultivated land area, grain sowing scale, and total grain output, GDP will decrease by an average of 0.2344 %, 0.1699 %, and 0.1424 %, respectively. In terms of estimation results at the county level, for every 1 % increase in total grain output, GDP will decrease by an average of 0.0824 %. (3) The curse effect mainly comes from the main grain production areas, and the results show that in the county–level studies, for every 1 % increase in total grain output in main grain production areas, GDP will decrease by an average of 0.0889 %. Overall, the regression results of total grain output at the provincial and county scales are relatively similar. (4) The poverty degrees and grain output levels in counties show a superposition trend with the curse effect. (5) The resource curse is caused by the effect of inhibiting the process of urbanization, crowding out the other industries in the main grain production areas, as well as the restrictions on the use of farmland and the reduction of grain price, so the economic development of regions with high grain output is relative slow. Based on these observations, this study proposes countermeasures to break the curse.