Academic research on grain work in the anti-Japanese base areas has clarified the grain institutional system in these areas, but has paid less attention to the practical implementation of these institutions. To explore how grain institutions were implemented at the grassroots level, this paper selects grain work in Mingzi Village as a micro case study. Mingzi Village is a mountainous village on the outskirts of Pingyao County, Shanxi Province, which belonged to the Taiyue Base Area during the War of Resistance Against Japan. Recently, a batch of account books from the anti-Japanese village office was discovered in the village. Based on the content of these account books, combined with relevant documents on grain work from the Taiyue District and Pingyao County, the development process of grain work in Mingzi Village can be reconstructed. In terms of burden distribution, Mingzi Village used estimation methods before and in 1942, with grain and funds allocated to households in a rather arbitrary manner. Between July and August 1943, the village implemented the rational burden method for the first time. Through investigations and democratic appraisals, burden scores were calculated, and the amounts of grain and funds for each household were determined accordingly. Although the investigation and appraisal that year were not thorough, with instances of income concealment and score suppression, subsequent investigations and appraisals were conducted multiple times. By 1945, the scoring process had become more in-depth and relatively fair. At this point, the village’s burden distribution transitioned from arbitrary allocation to a progressive taxation system. In terms of public grain collection, Mingzi Village achieved an efficient and orderly process in 1945. That year, summer grain, autumn grain, and fodder were all allocated based on burden scores, with each household’s share determined in advance. Once collection began, the task was completed quickly, with 90% of the public grain collected within 10 days, and the remaining arrears paid within two months. Regarding grain supply, starting in 1943, a large number of county- and district-level troops and cadres consumed grain in Mingzi Village. Initially, these county and district cadres mainly used IOUs for grain and ran up debts, failing to strictly adhere to grain regulations. Beginning in August, under strict supervision from the Taiyue District and enhanced management by the First District Office, most cadres shifted to using rice vouchers for grain procurement. The case of Mingzi Village illustrates that there were many gray areas in the grassroots implementation of grain institutions, such as score suppression during investigations and appraisals, as well as the use of IOUs for grain. However, through the management and oversight by the district office and other authorities, grain work in Mingzi Village was improved, achieving a considerable degree of institutionalization in links such as scoring, collection, and expenditure.