Background & Aims: Cancer is a major public health problem in many countries of the world and the third leading cause of death in developing countries. The most frequently diagnosed cancers in females and males are breast and lung cancers respectively. The aim of this study was to investigate the pattern of age distribution and the frequency of different cancers in East Azerbaijan province during the year 2009. Methods: This descriptive analytic study was performed by community based method on 5455 new cancer cases obtained from cancer registries in East Azerbaijan province in 2009. Characteristics of all registered cancers (including age, sex, and etc) were collected in a form. Then data were summarized and coded using the International Classification of Disease (ICD). Data were analyzed by SPSS software. The 95% confidence interval of the study Variables were calculated using Excel software. Results: Among 5455 cases, 3189 ones (58.5%) were males and 2256 ones (41.4%) were females. Mean age of cancer incidence was 57.3 ± 18.5 years. About 47.8% of malignancies occurred in ages over 60 years and 52.2% below 60 years. Among men, 57.8% of all cancers occurred in the age group of 60-70 years but in women 53.5% of them occurred in the age group of 50-60 years. Mean age at diagnosis was significantly higher (P<0.001) among males (60 years, 95%CI: 59.7-60.9) than females (53 years, 95% CI: 52.2-53.8). The 10 most common cancers among males and females were stomach (15.5%) and breast (20.9%) cancers respectively. Conclusion: More than half of all registerd cancers in the province were in the age group of above 60 years. Stomach and breast cancers are the most common malignancies of this region and occur most frequently during the 7th and 5th decades of life respectively. Comprehensive and complementary studies for recognizing relevant factors are among the priorities of health system research in this province.