OBJECTIVES: In 2010, lung cancer accounted for $12.6 billion in total direct medical costs. We examined the healthcare utilization and costs in elderly lung cancer patients with and without pre-existing COPD. METHODS:  Using SEER-Medicare data, we identified patients with lung cancer between 2006 to 2010, > 66 years, and continuously enrolled in Medicare Parts A and B in the 12 months prior to cancer diagnosis. Pre-existing COPD in lung cancer patients were identified using ICD-9 codes. Healthcare utilization and costs were categorized as inpatient hospitalizations, skilled nursing facility (SNF) use, physician office visits, ER visits, and outpatient encounters for every stage of lung cancer. The adjusted analysis was performed using a generalized linear model for healthcare costs and a negative binomial model for healthcare utilization. RESULTS: We identified 66,963 patients with lung cancer. Of these, 22,497 (33.60%) had documented COPD before lung cancer diagnosis. Healthcare utilization and costs were significantly higher in the COPD group compared to the Non-COPD group, increasing for every stage of lung cancer. Stage IV lung cancer patients with pre-existing COPD had the highest adjusted utilization per 100 person-months compared to the Non-COPD group (hospitalizations: 49.5 stays vs 31.24 stays, p<0.0001; SNF: 9.34 stays vs 4.78 stays, p<0.0001; physician visits: 2311.94 visits vs 681.84 visits, p<0.0001; ER: 56.58 visits vs 33.26 visits, p<0.0001; outpatient encounters: 2825.73 visits vs 2422.26 visits; p<0.0001). Similarly, the adjusted costs per person-month among stage IV lung cancer patients in the COPD group were highest compared to the Non-COPD group (hospitalizations: $3925.36 vs $2537.42, p<0.0001; SNF: $730.26 vs $380.49, p<0.0001; physician visits: $1169.49 vs $336.39, p<0.0001; ER: $199.71 vs $131.03, p<0.0001; outpatient encounters: $16021.90 vs $14025.50, p<0.0001).  CONCLUSIONS: Healthcare utilization and costs among lung cancer patients with pre-existing COPD was approximately two to three times higher than the Non-COPD group.