Objective : The aim of this study is to evaluate the synergistic effects of Traditional Korean Medicine with Gefitinib chemotherapy on a non small cell lung cancer. Methods : A 61 year-old male patient diagnosed with left non small cell lung cancer stage IIIb (T2aN0M1a) was admitted to East-West Cancer Center (EWCC) on Apr. 2012. He received Gefitinib chemotherapy since 20th June. 2011. He suffered from many complication like as skin toxicities, peripheral neuropathy, lassitude, diarrhea and so on. He was treated with Traditional Korean Medicine consisted of herbal medicine, acupuncture, and moxibustion. The symptoms were measured by Common Terminology Criteria for Adverse Events (CTCAE version 3.0) and visual analogue scale (VAS). Performance status was measured by Eastern Cooperative Oncology Group (ECOG). Results : TKM consisting of acupuncture, moxibusion, herbal medicine significantly alleviated Gefitinib induced complication. Quality of life was also significantly improved. Conclusion : This case study suggests that TKM would beneficial to adverse effects such as skin toxicities, peripheral neuropathy, lassitude from gefitinib.