This study explores international graduate students' experiences of content-language integrated learning (CLIL) at a university in Korea. This study focuses on a course that allows international students to simultaneously learn the Korean language and content knowledge. Korean as a medium of instruction (KMI) was applied to 16 international graduate students in two graduate courses during the 2021 Fall semester. The survey examines the perception and satisfaction of students' experiences in the KMI classes. Among survey participants, interview applicants were selected for in-depth interviews. Study results showed that international graduate students developed content knowledge through KMI classes. They also improved their Korean language ability. Overall, international students were generally satisfied with KMI classes. However, it is difficult for international students to dramatically enhance their Korean academic proficiency within one semester. Recommendations are provided on effectively conducting CLIL classes, such as KMI for international students in higher education.