© The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. Introduction: Tobacco use among persons living with HIV represents an important risk factor for poor treatment outcomes, morbidity, and mortality. Thus, efforts designed to inform the development of appropriate smoking cessation programs for this population remains a public health priority. To address this need, a study was conducted to longitudinally assess the relationship between intention to quit smoking and cessation over the 12-month period following initiation of HIV care. Methods: Patients initiating HIV care at a large inner city safety net clinic were enrolled (n = 378) in a 12-month prospective study. Audio computer-assisted self-interviews were conducted at baseline, and at 3, 6, 9, and 12 months post-enrollment, and HIV-related clinical data were collected from participants' electronic medical records. Variables of interest included intention to quit smoking, 7-day point prevalence smoking abstinence (biochemically verified), and stage of HIV. Data were collected in Houston, Texas from 2009 to 2015. Results: The sample was 75% male and 62% Black. Findings indicated that intention to quit smoking increased between baseline and 3 months, and subsequently trended downward from 3 to 12 months. Results from linear and generalized linear mixed models indicated that participants with advanced HIV disease (vs. not advanced) reported significantly (p < .05) higher intention to quit smoking at 3, 6, and 12 months post-study enrollment. A similar though nonsignificant pattern was observed in the smoking abstinence outcome. Conclusions: HIV treatment initiation appears to be associated with increases in intention to quit smoking thus serves as a potential teachable moment for smoking cessation intervention. Implications: This study documents significant increases in intention to quit smoking in the 3-month period following HIV care initiation. Moreover, quit intention trended downward following the 3-month follow-up until the 12-month follow-up. In addition, a marked effect for HIV disease stage was observed, whereby participants with advanced HIV disease (vs. those without) experienced a greater increase in intention to quit. HIV treatment initiation appears to be associated with increases in intention to quit smoking, thus serves as a crucial teachable moment for smoking cessation intervention for people living with HIV.