Stomach cancer is the most common malignant tumor in Korea. This study includes 900 stomach cancer cases which were collected at the Departrnent of Surgery, St. Marys Hospital, Catholic University medical College over the period from 1980 to 1991. The patients are divided into two groups: Those treated during the period between 1980 and 1986 - first group and the period between 1987 and 1991 - second group. We followed each patient and then analysed each patient's record using guidelines from the Stomach Cancer Study Group of Korean Surgical Society. There were 889 adenocarcinomas (98.8%), 5 malignant lymphomas (0.5%), 5 leiomyosarcomas (0.5%) and 1 leiomyoblastoma (0.1%). There were 378 patients in the first group and 522 in the second group. The number of second group patients was 1.4 times as many as compared to the first group. Peak age incidence was 6th decade (32%) and male to fema]e ratio was 1.8:1. The difference about age and sex between groups was insignificant. The number of patient under 35 years old was 87 cases (9.7%), Tumor locations were antrum (62.8%), body (27.4%), cardia (5.3%) and whole stomach (3.7%). The tumor location of the second group is more proximal portion of stomach than first group. Operation procedures performed were subtotal gastrectomy (69.1%), total gastrectomy (18.7%), bypass gastrojejunostomy (4.6%), exploratory surgery (6.3%) and proximal gastrectomy (0.8%) and so gastric resection rate was 88.6%. Total gastrectomy of the second group has increased compared to first group, while exploratory surgery has decreased. Regional lymph node metastasis was seen in 60.8% of all cases. Rate of regional lymph node metastasis according to tumor depth were as follows; 16% in T1, 48.4% in T2, 77.3% in T3 and 92.5% in T4, There were 162 cases of early gastric cancer (EGC 18%): 14% in the first group, 20% in the second group. The rate of EGC has significantly increased every year (p<0.05). Overall 5-year-cummulative survival rate was 55.8%. Overall 5-year-cummulative survival rates according to stage were as follows: 98.6% in stage I a, 89.6% in I b, 67% in II, 58.4% in llIa. 29.4% lIlb and 14% in stage IV. overall 5-year-cummulative survival rates according to depth were as follow: 93.9% in Tl, 85% in T2, 48.8% in T3 and 12.4% in T4. Hospital death rate was 1.5%.