Background: Clinical practice guidelines for mild traumatic brain injury (mTBI) management call on family physicians to proactively screen and initiate treatment for mental health complications, but evidence suggests that this does not happen consistently. The authors aimed to identify physician-perceived barriers and facilitators to early management of mental health complications following mTBI. Methods & results: Semi-structured interviews based on the Theoretical Domains Framework (TDF) were conducted with 11 family physicians. Interview transcripts were analyzed using directed content analysis. Factors influencing management of mental health post-mTBI were identified along five TDF domains. Conclusion: Family physicians could benefit from accessible and easily implemented resources to manage post-mTBI mental health conditions, having a better defined role in this process, and formalization of referrals to mental health specialists.