An initial survey conducted with international students at the National Tsing Hua University (NTHU) revealed their poor or basic level of Chinese language and the lack of motivation among them to continue learning Chinese. This was due to several factors like no interest, lack of time or time conflicts. Chinese language is a barrier for their performance while living in a Chinese speaking country as they have stated in the survey. Additionally, in the future the lack of Chinese language skills could limit any intention of employment, especially for those international students who after completing their degrees are looking forward to developing a professional career in Taiwan or in any other Chinese speaking country. This study presents a mobile game-based system that aims to support the Chinese language speaking and motivation of the international students in a Chinese environment. The game contains strategies based on exploring tasks and intercultural interaction tasks in which the players perform real-life situations. Missions are completed visiting specific buildings on the NTHU campus and interact directly with local Taiwanese people in order to solve the tasks required in the game. The interaction process is done completely in Chinese with the assistance of mobile devices to access the game system. The system contains basic sentences and vocabulary needed to complete the task. Immediate feedback is given to the players in the form of a test that assess information related to the mission. The experiment results showed that participants, all international students studying at NTHU, felt highly motivated to keep using the game system for an extended period of time and even suggested it to be part of the Chinese language classes. Most of the participants in this study expressed that they are interested in learning Chinese. They also rated the game as a useful tool for Chinese learning; particularly for the interaction with native speakers present in all the tasks of the game, which helped them to improve their Chinese speaking skills and to give them more confidence. Finally, all of the items evaluated in the Chinese knowledge section had an increase (or at least remained equal) in the correct answers compared to the pre-test. This confirms that the game system can support Chinese language learning and help the international students to increase their understanding and knowledge of the Chinese language.