Abstract: Objective To study the impact factors of psychological distress in patients with lung cancer-associated pain. Methods The cross-sectional study was applied to lung cancer pain patients received treatments in Cancer Center of West China Hospital of Sichuan University in Chengdu from July 2011 to December 2011 by distributed questionnaires. The general information of the patients, Brief Pain Inventory （BPI） and the Hospital Anxiety and Depression Scale (HADS) were included in the questionnaire to evaluate the states of distress, pain and the factors related to the total distress score. Results Totally 172 effective questionnaires were obtained in 200 delivered questionnaires. The average pain score of the patients was 3.67±1.27. The Spearman correlation analysis showed that depression score, anxiety score, distress score were positively correlated with the pain intensity (P<0.05). Patients with positive anxiety symptom was 29.0%, the depression was 29.0%, and distress was 68.6%. Mutiple linear regression analysis showed that gender (β=0.152, P=0.024), age (β=-0.150, P=0.023), marital status (β=-0.239, P=0.000) could affect the total score of distress; gender (β=0.154，P=0.013), age (β=-0.165, P=0.007), the clinical pathological stage (β=0.155, P=0.011) could affect the anxiety score; marital status (β=-0.133, P=0.047) could affect the depression score. Conclusion The genders, age, marital status of the patients are related to the psychological distress of lung-cancer-pain patients.