Targeted therapy is a milestone of tumor drug treatment in the 21st century. Unlike traditional chemotherapy drugs, which are “indistinguishable from the enemy”, targeted drugs work on different targets of tumors, with relatively less impact on normal tissues, higher accuracy, and high efficiency and low toxicity. There are many types of targeted drugs: those targeting a specific gene, receptor, protein or enzyme, those targeting single or multiple targets, those used in combination with chemotherapy, those used alone, those taken orally, and those used intravenously. Currently, the main targeted drugs for the treatment of non-small cell lung cancer are the tyrosine kinase inhibitors gefitinib (ERSA) and erlotinib (Troche), which act on the epidermal growth factor receptor (EGFR), the monoclonal antibody bevacizumab (Anvitin), which acts on the vascular endothelial factor receptor (VEGFR), and the anti-EGFR cetuximab (Epiduo). Bevacizumab (Avastin) and cetuximab (Epiduo) are not used clinically in advanced non-small cell lung cancer because of their high price, intravenous administration, and the need to combine them with chemotherapy. ERSA and Trocet are widely used in clinical practice because of the convenience of oral administration, relatively low price and low side effects. Both ERSA and Trocet target EGFR and belong to the same class of drugs. The median survival of patients with EGFR mutations treated with ERSA and Trocet is more than 23 months, compared to 10-15% for wild-type patients. Therefore, EGFR mutated advanced non-small cell patients can be considered first for Eressa or Troche if their financial condition allows. In contrast, for patients with EGFR wild type or unknown EGFR status, it is not advocated to prefer ERSA and Troche because the efficacy of wild type is significantly lower than that of chemotherapy. Since the efficacy of second- or third-line chemotherapy for advanced non-small cell lung cancer is unsatisfactory and patients are not in good physical condition at this time after prior chemotherapy or other antitumor therapy, for these patients, irrespective of EGFR mutation, Eressa or Troche may be an option with overall efficacy similar to that of chemotherapy. Although Erisa and Troche act on the same target, clinical trials have shown that Troche is effective in treating advanced non-small cell lung cancer in the West, while Erisa is not as effective, and therefore Erisa is not recommended as second-line therapy in Europe and the United States. Among patients with unknown EGFR status, women, nonsmokers, and adenocarcinoma patients were found to have good efficacy with Eressa and Troca, which is called a superior population. The reasons for this were found to be the high incidence of EGFR mutations in these populations. Finally, it should be emphasized that Erisa and Troche are not used for postoperative adjuvant therapy in patients with EGFR mutations and are not recommended in combination with chemotherapy. In addition, it is not recommended to use Troche after failure of Erisa (except in isolated cases) and Erisa after failure of Troche.