Endocrine cell (EC) in 11 cases picked up from 56 cases of gastric carcinoma were observed by double immunohistochemical method using chromogranin A(CgA) and proliferating cell nuclear antigen (PCNA) . The endocrine cells were recognized by a antibody to CgA and the proliferative activity by a monoclonal antibody to PCNA. 11 cases CgA positive GC cells with PCNA incorporation was in 51/4069 (0-3%) with an average 1.25%. By contrast, PCNA reaction was positive in 31.9±14.7% of CgA negative GC cells. It suggests that there were a few cell in S and G₁ phase and most of them in G₀ phase.