Background: Cancers of gastric and esophagus are the most frequent gastrointestinal (GI) tract cancers in Iran. This study aimed to analyze time trends of GI tract cancers in Guilan province by gender and age to provide solid scientific evidence for cancer prevention and control. Materials and Methods: The data were obtained from the Guilan Cancer Registry System and Guilan Provincial Health Center, over the 15 year period between 1997 and 2011. Crude incidence and age standardized (AS)incidence rates were calculated and annual percent change was estimated by Joinpoint software for long term trend analysis. Results: During the study period, 8,332 cases of GI malignances with a male to female ratio of 1:1.73 were registered in Guilan province. The AS rates for esophageal, gastric, colon and rectal cancers were 5.97, 14.5, 7.59 and 3.58 per 105 respectively. While the trend was declining and relatively constant for esophageal and gastric cancer, respectively, the incidence trend for colon and rectal cancers was of increase over the period of the study. Conclusions: The results indicated that the incidence of GI cancers was relatively low in Guilan province compared to neighboring provinces. An effective cancer control program including prevention measures, early detection and effective treatment needs to be implemented to reduce cancer morbidity and mortality.