The purpose of this study was to explore the factors that influenced the oral classroom participation of six Korean students attending graduate school in the US, and how these factors impacted their oral interaction in class discussions. Data came from formal and informal interviews and class observations over the course of the semester. Participants included three masters' students and three doctoral students, two males and four females, enrolled in two education courses. The study showed that multilayered factors, including the students' English proficiency, differences in sociocultural values and educational practices between two cultures, individual differences, and classroom environment were intertwined, and each factor singly and together influenced the students' oral participation in class discussions (OPCD). While the students in this study demonstrated many cultural similarities with other Asian students, they also revealed unique Korean cultural features. Regardless of their length of study in the US, all students felt challenged to participate in whole class discussions. However, in small group discussions, participation varied greatly among the individual students. In particular, the female students, with one exception, participated more actively than the male students. The findings suggest pedagogical implications for promoting the oral classroom participation of Asian international students, especially Korean students. (Contains 2 tables.)