Previous studies have reported that international students in the US experience unique difficulties and acculturative stress related to cultural differences, language barriers, academic pressure, and interpersonal relationships (Mallinckrodt & Leong, 1992). Berry, Kim, Minde, and Mok (1987) defined this "acculturative stress" as "one kind of stress, that in which the stressors are identified as having their source in the process of acculturation." (p. 492) "Acculturative stress" refers to a response by individuals to life events that stem from intercultural contact (Berry, 2006). A focus on Korean international students is important because the number of Korean international students in the US has grown rapidly from only 290 in 1979 (Klineberg & Hull, 1979) to 68,047 in 2013-2014 (Institute of International Education, 2014). Having social support is especially important for the mental health of international students who are from collectivist cultures, such as those from East Asia, including Korea, because people from the collectivist cultures emphasize the social relationships and the networks created between people around them (Markus & Kitayama, 1991). Therefore, the present study explored the acculturative stress of Korean international students by focusing on their characteristics and different sources of social support. The author examined the effects of demographic variables (gender, age, and degree sought) on acculturative stress and then investigated which sources of social support (i.e., new friends in the United States, community activities, religious places, student organizations, international student center, direct family, secondary families, and old friends in home country) are related to acculturative stress when controlling for those demographic variables.