Informed by Poststructuralist Theory, this study investigated the impact of stereotyped notions of English on three doctoral Asian teaching assistants' (TAs) professional identities development as instructors at a US university. This article employed a qualitative approach to examine the Asian TAs' views of standard and stereotyped views of English language in academic settings and its influence on their professional identities. Using interviews as the primary data source, this article found that stereotyped notions of English language are materialized as monotone English and accented English for the three Asian TAs who are constantly monitoring and changing their language use particularly in their professional workplace. Drawing from this finding, discussions and implications focussed on the marginalization of Asian TAs' expertise in the content knowledge, problematization of standard English language, and its relation to the larger sociopolitical world.