Purpose The objective of this study was to determine how to optimize implementation of tobacco cessation treatment interventions in cancer care by (1) investigating the feasibility and acceptability of a multi-level approach to tobacco cessation treatment intervention, (2) identifying barriers and facilitators to implementation, and (3) eliciting additional strategies to improve implementation of the intervention. Methods We conducted qualitative interviews with oncologists ( n = 15) from one large academic health center in the Southeastern United States. We asked about their knowledge, attitudes, and current practices regarding tobacco use screening and treatment. We also asked about two proposed strategies to support implementation of tobacco cessation treatment: (1) developing a registry of tobacco users in collaboration with the state-run tobacco cessation program, and (2) providing on-site tobacco cessation counseling from trained professionals. Results Oncologists saw addressing tobacco use as valuable; however, they felt restricted from consistently addressing tobacco use by multi-level barriers such as workload, electronic health record (EHR) design, patient anxiety, and low self-efficacy for treating tobacco dependence. Oncologists responded positively to on-site treatment and felt this strategy would increase treatment accessibility and enhance engagement. Reaction to developing a registry of tobacco users was mixed, with concerns regarding lack of oncologist involvement and patient privacy expressed. Other suggested strategies for supporting implementation of tobacco cessation treatment included reducing referral complexity, establishing financial or quality incentives for oncologists, and leveraging existing EHR tools to facilitate integration of cessation interventions into clinic workflows. Conclusions We identified several challenges to implementing tobacco use treatment in cancer care; however, we considered strategies to overcome these barriers that were viewed as feasible and acceptable. Our work highlights the importance of engaging stakeholders in implementation efforts. Future work should explore the impact of the implementation strategies identified in this study. Plain Language Summary Tobacco cessation significantly improves cancer patients’ treatment outcomes, quality of life, and chances of survival; however, tobacco cessation interventions are not routinely delivered in oncology care. Interviews with oncologists identified barriers to delivering tobacco cessation interventions at multiple levels. Suggested strategies for overcoming these barriers included simplifying cessation intervention processes, establishing incentives for oncologists to address tobacco use, and using the electronic health record to support intervention activities. Oncologists generally supported implementing on-site tobacco cessation counseling for cancer patients. Although there was support for developing a registry of tobacco users with an external tobacco cessation program, more reservations were expressed. Our work identifies several stakeholder-endorsed strategies for implementing tobacco cessation interventions in cancer care. Future research should test the effectiveness of these strategies.