Abstract: Climate change has become an important factor affecting the stability of agricultural production and national food security. As one of China’s three major staple crops, rice production and circulation are directly related to food self sufficiency, market price stability, and the protection of farmers’ incomes. Therefore, a systematic analysis of the impacts of climate change on rice supply and circulation patterns is of considerable theoretical and practical significance. Based on a single country, multi-regional computable general equilibrium model of China (SinoTERM), this study examines the effects of climate change on rice supply, prices, and circulation patterns under different combinations of Shared Socioeconomic Pathways (SSPs) and Representative Concentration Pathways (RCPs), with a particular focus on the critical role of the Northeast Black Soil Region in the national rice supply system. The results show that rice yields across China are projected to decline significantly from 2030 to 2050, accompanied by rising prices, reduced regional self-sufficiency, and an expansion in inter-regional circulation. Jiangsu, Jiangxi, and Hunan provinces in the middle and lower reaches of the Yangtze River Plain, together with the Northeast Black Soil Region, account for 9.36%, 8.89%, 10.58%, and 6.32% of total national rice circulation, respectively. Rice from the Northeast Black Soil Region is mainly transported to Shandong, Guangdong, Henan, and Zhejiang provinces, which account for 5.05 %, 4.84 %, 4.10%, and 4.07% of total outflows from this region. Under climate change conditions, rice outflows from the Northeast Black Soil Region increase compared with those under corresponding socioeconomic scenarios, with an additional 2.027 to 2.187 million tons. Among these increases, Heilongjiang accounts for 42 %, followed by Jilin with 32%, Inner Mongolia with 16%, and Liaoning with 10%. This study reveals the long-term safeguarding role of the Northeast Black Soil Region in ensuring national rice supply under climate change, and provides a scientific basis for the formulation of black soil protection policies and the optimization of national grain reserves. The findings have important practical implications for addressing climate risks and ensuring national rice supply and demand balance and food security.