Approximately 10 students from Hiroshima University, most of whom have learned German for two or three semesters, participate in a summer course held at the University of Hamburg every year. Those students study German with learners from Korea, Taiwan, and other parts of Japan. After the course, many of them comment that their vocabulary was insufficient, or that the Korean and Taiwanese students could speak German better. It is a fact that many of the students from Korea and Taiwan attending this summer course are majoring in German in their own countries, whereas our students usually are not. This is certainly one reason for the Japanese students' perceived or actual inferiority in the language. However, there are other reasons for the problem, such as the textbooks used, styles of communication in their native languages, motivation and learning styles, and personal attitudes. This article reports on a quantitative comparison of the vocabulary in Japanese and Korean German textbooks, which is part of wider research into the German textbooks used in East Asian countries. Compared with Korean textbooks, Japanese textbooks use a smaller number of vocabulary items. On the other hand, the Japanese textbooks contain more common or everyday vocabulary than the Korean textbooks. Altogether the four Korean and four Japanese textbooks investigated here contain only 140 common everyday words, and Korean textbooks contain twice as many words as Japanese textbooks. The findings show that learning a larger amount of vocabulary in Korea depends to a great extent on textbooks, and that while Korean learners may acquire a large vocabulary by the end of their studies, Japanese textbooks offer a much smaller vocabulary consisting of common everyday words.