Background: Stomach cancer is the fourth most common cancer and the second leading cause of cancer-related death through the world. It is predicted that the number of new cancer cases will be more than 15 million cases by 2020. Regarding the lack of studies on this topic in the country, we have thoroughly examined the patho-epidemiology of stomach cancer in Iran. Materials and Methods: In this cross- sectional study data were collected retrospectively reviewing all new stomach cancer patients in Cancer Registry Center report of health deputy for Iran during a 6-year period (2003-2008). The study also examined the morphology of common stomach cancers. Trends in incidence and morphology underwent joinpoint regression analysis. Results: During the six-year period, a total of 35,171 cases of stomach cancer were registered. Average age standardized rate for females and males were equal to 7.1 and 15.1 per 100,000 persons, respectively. Most common histological type was adenocarcinoma, NOS with 21,980 cases (62.50). The annual percentage change (APC) in age-standardized incidence rate (per 100,000) was increase in both females and males at 11.1 (CI: 4.3 to 18.3) and 9.2 (CI: 5.2 to 13.4), respectively. Conclusions: According to our results, the incidence of gastric cancer is increasing in Iran, so further epidemiological studies into the etiology and early detection are essential
