For the gastric cancer, paclitaxel is recommended as salvage standard treatment. Afatinib is a novel, potent, small ErbB family blocker that covalently binds and irreversibly blocks signaling through activated EGFR, HER2 and ErbB4 receptors, as well as the transphosphorylation of ErbB3. The investigators suggest a randomized phase II trial of afatinib plus weekly taxol(paclitaxel) for previously treated EGFR positive gastric cancer patients. The aim of current trial is to evaluate the antitumor efficacy of afatinib for target enriched patients in gastric cancer.