Lung cancer is a disease with strong stigma due to stigmatization around smoking. Reducing stigma could be favorable for patients but requires to identify factors influencing this stigmatization. This study aimed to analyze people’s acceptability judgments regarding smokers’ behaviors concomitant to a lung cancer diagnosis. This study used a quantitative method to identify variables involved in one’s judgment, based on a comprehensive combination of scenarios rated by participants on an acceptability scale. Scenarios were built using factors putatively influencing participants’ judgment of a woman character diagnosed with lung cancer, including smoking habits, type of diagnosis/prognosis, and postdiagnosis smoking behavior. Two different samples were studied: 132 community individuals and 126 health professionals. Data were analyzed using within-subject factorial analysis of variance and t tests. In both samples, the postdiagnosis behavior had large effect sizes, with smoking cessation being more acceptable than other smoking behaviors. Other factors, including diagnosis and smoking habits, had significant influences on participants’ judgments, with small to medium effect sizes. Diagnosis had a stronger effect size when interacting with postdiagnosis behavior, as the acceptability by health professionals of continuing smoking was almost doubled when the character had advanced rather early stage cancer. The lesser the smoking behavior, the better the acceptability. However, advanced cancer stage attenuated the poor acceptability of smoking in health professionals, and, to a lower extent, in community individuals, as these participants’ attitudes were more permissive when the patient had advanced cancer. This could substantiate the higher distress recently reported in early stage lung cancer patients. This study illustrates with quantitative data the stigmatization toward lung cancer patients when smoking subsists. In terms of implications for practice, these findings could allow to identify, as early as the time of diagnosis, the persons the most at risk of being stigmatized, in order to reduce the impact of stigma. Indeed, according to this study, the profile of the most stigmatized individuals would be those with early stage lung cancer who smoked heavily before diagnosis and who continue smoking after diagnosis.