Self-diagnosis is an increasingly widespread phenomenon as mental health information becomes more available and commonplace through social media. College students often encounter struggles with mental health, and being frequent users of social media may make them more susceptible to seeking out mental health information on social media platforms instead of through professional channels. Through semi-structured interviews, the present study aimed to examine students’ perceptions of online mental health discourse, perceptions towards formal diagnosis and practitioners, and the consequences of self-diagnosis. The thematic analysis found that many students are apprehensive of self-diagnosis because it can be biased, based on incorrect knowledge from social media, and because it can threaten the legitimacy of official diagnoses. Among the smaller subset of students who self-diagnosed, many echoed the concerns their peers posed about self-diagnosis but also felt that learning about oneself in any way is beneficial, even if that comes through self-diagnosis. Lastly, participants discussed that self-diagnosis is acceptable in situations where one does not have access to professional mental health care, meaning the legitimacy of a self-diagnosis is circumstantial. Overall, college students are hesitant to categorize themselves as self-diagnosed and frequently advocate for professional assessment, suggesting that “self-diagnosed” has arisen as a label that students are reactive towards. Students may identify with a certain condition even if they do not see themselves as ‘self-diagnosed,’ and this distinction was apparent among numerous participants as they discussed their mental health experiences and exposure to it on social media. While college students are largely skeptical of self-diagnostic information on social media, this does not mean they do not self-diagnose, and the content may still impact how they view the legitimacy of self-diagnosis.