The purpose of this study was to evaluate the frequency of Her2 oncogene overexpression and concordance between the results for Her2 protein expression and gene amplification. Materials and Methods:  A total of 65 retroprospective cases with gastric adenocarcinoma, including biopsy and resected specimens obtained between July 2015 to December 2017, were analyzed. Here, ERBB2 is linked to gastric adenocarcinoma.