Introduction: Sleep disorders are relatively common in oncology and it can worsen the quality of life of patients with cancer and especially lung cancer. Aim: Assess sleep disorders in patients with lung cancer. Methods: Cross-sectional study conducted during 2 months among patients diagnosed with lung cancer in the department of pulmonology in 2 university hospital centers. Patients answered 2 questionnaires: Spiegel questionnaire(score/30) and Pittsburgh quality of sleep index(PSQI: score/21) which was administrated by the same investigator. Components of PSQI are: Subjective sleep quality, Sleep latency, Sleep duration, Sleep efficiency, Sleep disturbance, Use of sleep medication, Daytime dysfunction. Sleep disorders were diagnosed if Spiegel score was Results: 43 patients were included (sex-ratio M/F=6.16;average age=62±11 years). The cancer was confirmed histologically in 90% (4 patients were being explored): adenocarcinoma in 67%, squamous cell carcinoma in 23% and small cells carcinoma in 10%. For cancer staging: 67% were stage IV, 26% stage III and 7% stage II. Curative surgery was performed in 3 cases. The average score of Spiegel questionnaire was 18±5 and that of PSQI was 11±5. Sleep disorders were detected in 26% with Spiegel score and in 50% with PSQI score and were correlated to age (p=0.43 and =0.21 respectively). Sleep quality was worsened in 65%, Sleep latency was extended in 67%, sleep duration was reduced in 58%, sleep wasn’t efficient in 39%, sleep was disturbed in 70%, sleep medication was used in 35% and there was daytime dysfunction in 32% of cases. Conclusion: Half of patients with lung cancer had sleep disorders. Psychological care is needed to improve their quality of life.