In this globalization era, study abroad program are everywhere worldwide. Many international students from all around the world participate this program in order to study in a whole new environment and gain new experiences. The program allows the international and local students interact to one another.The interaction woud likey cause culture shock and some people considered that as challenges. Meanwhile, international students, during the study, face different challenges. The aim of this study is to find out the international students perspective towards sources of culture shock as a challenge and their strategies to overcome those sources. This study was conducted in one private Islamic University in Yogyakarta. The researcher used qualitative approach and apply case study as the design. Case study was used because it is aimed to find out about certain phenomenon at a certain time. The participants of this study are one Taiwanese student from exchange program and oneThai student who took a bachelor degree. After taking the data, the result of this study showed that the sources of culture shock come from daily life basis and academic basis. The researcher divided the challenges into seven different items, which are; weather, outfit, people’s character, custom, food, traffic, and language differences. These two participants have their own ways to overcome the challenges. Most of the ways to overcome the challenges is to accept and adapt with it.