Patients with inoperable, locally advanced or recurrent and/or HER2-positive metastatic gastric or gastro-esophageal junction cancer, with no prior treatment for metastatic disease are to be recruited in the study. In the current study, the efficacy and safety of Trastuzumab in combination with Capecitabine/Docetaxel will be evaluated in Chinese patients with HER2 positive advanced or recurrent gastric cancer.60 patients could provide adequate precision rather than controlling type I&II error. Assuming the target PFS is 6.7m, 60 patients will give 90% CI of (5.5, 8.4). Considering the 5% drop out rate, 65 patients will be enrolled.