In 2016, the Ministry of Education initiated the international teaching practicum program for pre-service teachers, but there lack relevant studies to explore the participants’ feedback on this initiative. The purpose of this study is to explicate the potential influence of the international teaching practicum experience on the pedagogical content knowledge of pre-service teachers through a case study at X University in Taiwan. This study used semi-structured interviews as the data collection method to gather the pre-service teachers’ opinions and to analyze the impact of international teaching internship practices. Three research results of this study are as follows. 1) international teaching practicum had various positive impacts on pre-service teachers’ PK. 2) International teaching practicum experience enhanced the high-order thinking of pre-service teachers. 3) The length of the international teaching practicum affected the richness of pre-service teachers’ learning experience, and there was some positive influence of learning from international teaching practicum on participants’ pedagogical content knowledge. Based on the findings of this study, this paper puts forward three suggestions: 1) establish a policy evaluation mechanism, 2) provide a more detailed guideline of ITP, and 3) deepen the influence of international teaching practicum among pre-service teachers. Those suggestions can serve as a reference for revising the international teaching practicum policy for pre-service teachers in Taiwan and further serve as an important reference for promoting the international education cultivation strategy for pre-service teachers in the future.