Tobacco use is common among homeless adults, yet few homeless shelters offer tobacco dependence treatment. Using a pre-intervention and post-intervention study design, we pilot tested the feasibility of a capacity building intervention that consisted of a 3.5-h training for shelter staff to provide cessation counseling. Staff (n = 12) and homeless clients (n = 46) completed questionnaires at pre-intervention, post-intervention (6 weeks), and at 12-weeks follow-up. Staff completed a questionnaire on tobacco-related knowledge, attitudes toward and practices around treating tobacco dependence, and self-efficacy in providing cessation counseling (score range 1-5). Clients completed a questionnaire on tobacco-related knowledge, attitudes toward tobacco dependence, and receipt of tobacco-related services from the program (score range 1-5). We used repeated measures linear regression analysis to examine change in scores over time. From pre-intervention to post-intervention, staff knowledge (β coefficient 0.4, 95 % CI 0.1-0.8) and efficacy (β coefficient 0.4, 95 % CI 0.2-0.7) in treating tobacco dependence increased. Client receipt of tobacco-related program services increased significantly from post-intervention to follow-up (β coefficient 0.3, 95 % CI 0.1-0.5). A brief capacity building intervention has the potential to increase tobacco-related interventions among clients in homeless shelters.