The purpose of this paper is to clarify the change in beef supply in Japan after the Russo-Japanese war. Both civilian and military demand for beef rose sharply during the period, and domestic cattle farming could no longer support Japan's growing demand for beef. Japan had expanded its empire by colonizing Korea in 1910 and occupying Shandong in 1924 as a result of the battle of Qingdao. These events made it possible to import cattle and beef from Korea and Qingdao to satisfy Japan's growing demand for beef. The results of this study reveal the following two important points. The first point concerns the actions taken to counter rinderpest. Import of cattle was associated with the risk of animal infection, especially rinderpest. Japan suffered repeated accumulation of rinderpest that accompanied to cattle import. These rinderpest epidemics became the key factor for declining imports of cattle from Quingdao, which were then replaced by imports of carcasses instead. However, imports from Korea did not decline despite the influx of the disease. This may be attributed to the high reputation enjoyed by cattle imports from Korea, not just as asource of beef but also as a farming cattle: cattle from Korea were also used as field labor. The second point is that there were distinct differences between the cattle reared in Japan itself and the beef imports, which led to differentiation in meat quality. During the period under study, Japan developed techniques for fattening cattle, which were mainly targeted at producing marbled meat for gyunabe. The imported beef and cattle were thus evaluated as being inferior to the fattened indigenous cattle. However, the supply of inferior and low-priced imported beef contributed towerd popularizing the custom of eating beef in Japan.