OBJECTIVES: Assess the cost-effectiveness of tyrosine kinase inhibitors (TKIs) on an EGFR+ NSCLC population under the Brazilian private healthcare system.  METHODS: A cost-effectiveness analysis (CEA), based on a Markov framework with monthly cycles, was performed to evaluate costs and effects of gefitinib versus erlotinib on an EGFR+ NSCLC population over a 1 year period. Outcomes measured were overall survival (OS), progression free survival (PFS), Quality Adjusted Life Years (QALYs) and total costs. Direct medical costs were assessed, including treatment and genome testing costs. Treatment costs were based on ex-factory prices and label defined posologies. Efficacy data was based on a meta-analysis by Gao et al. RESULTS: Gefitinib was equivalent to erlotinib regarding effectiveness outcomes, showing incremental results of 0, -0.02 and -0.01 for OS, PFS and QALY over a 1 year time horizon, respectively. Costs were significantly lower on patients treated with gefitinib than on those treated with erlotinib. On a scenario where genome testing was not performed gefitinib showed a total cost of R$ 21,580.56 (US$ 6,916.67) while erlotinib showed total costs of R$ 39,393.24 (US$ 12,626.04), resulting in an incremental cost of -R$ 17,812.98 (-US$ 5,709.29). Genome testing added R$ 1,000.00 (US$ 320.51) to both arms, resulting in R$ 22,580.56 (US$ 7,237.36) and R$ 40,393.24 (US$ 12,946.55).  CONCLUSIONS: Regarding effectiveness, both TKIs showed a similar profile. Those results are confirmed by a recent meta-analysis by Haaland et al. Therefore, in this economic model gefitinib and erlotinib showed similar efficacy profile with gefitinib representing a less costly treatment choice than erlotinib for the Brazilian private healthcare system.