Background: Continued smoking after receiving a diagnosis of cancer seriously affects disease prognosis and survival. The prevalence and risk factors of continued smoking among patients with newly diagnosed lung cancer are unknown in Taiwan. Purpose: The aims of this study were to assess the smoking status of patients with newly diagnosed lung cancer and to identify the characteristics that are associated with different smoking statuses. Methods: Baseline data of a longitudinal study on smoking behaviors after lung cancer diagnosis were analyzed in this study. Patients were consecutively recruited from three medical centers in northern Taiwan. A structured questionnaire and medical chart reviews were used to collect data. Multinomial logistic regression analysis was used to examine the factors associated with continuing to smoke after being diagnosed with lung cancer. Results: Among the 406 patients with newly diagnosed lung cancer who were recruited, 47.0% were never-smokers and 53.0% were ever-smokers. Among the second group, 38% were former smokers, 18% were recent quitters, and 44% were current smokers. Compared with former smokers, current smokers were more likely to be younger (OR = 1.05), to not exercise regularly (OR=2.74), to currently live with smokers (OR= 2.48), and to have lower self-efficacy for refusing to smoke (OR = 0.95). Compared with recent quitters, current smokers were more likely to have lower self-efficacy for refusing to smoke. Conclusions/Implications for Practice: A significant proportion of ever-smoker lung cancer patients in Taiwan will continue to smoke after receiving their diagnosis. Variables known to modify the risk factors associated with continued smoking such as regular exercise and better refusal self-efficacy should be considered and incorporated into future smoking cessation programs for patients with lung cancer.