Objective We assessed associations between electronic cigarette (e-cigarette) use and smoking-related measures among American Indians (AIs) who smoke. MethodsWe collected baseline survey and smoking biomarker data in a cohort of 375 adult AI smokers at a Cherokee Nation healthcare facility in Oklahoma. We used multivariate logistic and linear regression analyses to determine associations between e-cigarette use and smoking-related characteristics, including biomarkers. ResultsCurrent e-cigarette users were more likely than never users to report a quit attempt in the past 12 months (current vs never adjusted odds ratio (AOR) = 2.24 [95% CI 1.20-4.16]). Current and past e-cigarette users were more likely than never users to report a likelihood to quit smoking (current vs never AOR = 2.97 [95% CI 1.34-6.56]; past vs never AOR = 1.77 [95% CI 1.08-2.91]). E-cigarette use was not significantly associated with confidence to quit smoking, cigarette packs smoked per day, or cotinine levels. ConclusionsE-cigarette use was associated with previous and future quit attempts, but not with reductions in cigarette smoking or confidence in quitting. This suggests that many dual users might benefit from the addition of evidence-based smoking cessation treatments.