Objetive: Despite the fact that cancer is underreported in most Latin American countries, available data suggest that it has progressively become a major cause of concern throughout the region. To provide additional descriptive information on cancer incidence in the Northern Ecuadorian Amazon Basin (NEAB), different sources of data were used. Methods: Cancer cases from the NEAB in the period 1985-2003 reported by the National Cancer Registry (NCR) of Ecuador were used to calculate incidence rates. Incidence rates were obtained in periods of five-years and were compared with those found at national and international level. The population at risk was estimated according to two consecutive national censuses (1990; 2001). Results: 1 415 cases of cancer (858 women and 557 men) reported by the NCR were analyzed. The most frequent cancers in the NEAB are in line with those found at national level. During the period 2000-2003, the age-standardized rates (ASR) were highest for cervical and stomach cancer among women with 19.9 (IC95% 10.9 - 28.9) and 5.9 (IC95% 0.6 - 10.8) cancer cases per 100 000 habitants/year respectively. For men stomach cancer was the most frequent type with 7.7 (IC95% 2.3 - 13) cases per 100 000 habitants/year. The ASR of cervix cancer is among the highest reported by cancer registries internationally. About 50% of the cancer cases were diagnosed in people with primary education (6 school years) in both men and women. Conclusion: The analysis that evidenced a high underreporting rate, outlines first but incomplete insights into pattern of cancer incidence trends in NEAB. It will be of high importance for the health system to develop sound monitoring and registration practices to inform and generate evidence-based health policy and support comprehensive cancer care and its prevention without neglecting sociocultural aspects.