This study aimed to explore the experiences of Chinese EFL doctoral students in constructing their academic identities through critical argumentation in their thesis writing in an English as a Medium of Instruction (EMI) context. Data were collected through semi-structured interviews and document analysis. Narrative analysis was used to examine participants' thesis writing to gain insights into their experiences of academic identity construction. The results revealed that Chinese EFL doctoral students face challenges in developing a critical voice and authorial position, synthesizing multiple sources, and positioning themselves rhetorically in their writing. Furthermore, the results open possibilities for a broader understanding of academic writing that values international graduate student's educational background and cultural diversity in target English language discourse communities. While the narrative inquiry study on Chinese EFL doctoral students' academic identity construction through critical argumentation is insightful, there are several limitations to consider, mainly due to the small sample size of only two female Chinese respondents. Constructing Academic Identity through Critical ArgumentationThis study investigates how Chinese international doctoral students construct their academic identities by using critical argumentation in their thesis writing within an English as a Medium of Instruction (EMI) setting. The researchers collected data through semi-structured interviews and document analysis. In addition, they used narrative analysis to examine the participants' thesis writing and gain a deeper understanding of their experiences in developing their academic identities. The study's findings indicated that Chinese EFL doctoral students struggle to establish a critical voice and authorial position, integrate multiple sources, and strategically position themselves in their written work. This means that they struggle to express their opinions and ideas in their writing and use sources effectively to support their arguments. They also find it challenging to position themselves as experts in their field. The results highlight the need for a more comprehensive understanding of academic writing that considers international graduate students' educational backgrounds and cultural diversity in English language discourse communities. This means that academic writing instruction should be tailored to the needs of students from different cultural and linguistic backgrounds. The study has some limitations, particularly the small sample size, which only includes two female Chinese participants. This means the findings may not be generalizable to Chinese international doctoral students or students from other cultural and linguistic backgrounds.