Background: Primary melanomas of the digestive tract excluding oral cavity and nasopharynx are rare cancers and population based studies are sparse. We analyzed the Surveillance, Epidemiological and End Results (SEER) database in order to characterize this malignancy.Methods: SEER 17-registries database was analyzed for malignant melanomas of the digestive tract (the esophagus to the anus) from 1973-2005. Demographic variables analyzed included age, sex, race and marital status. Tumor variables included site, stage at diagnosis, treatment and histology. SEER*Stat and XLSTAT software were used for statistical analysis.Results: 472 cases were analyzed after various exclusions. Age-adjusted incidence rates were 0.04 per 100,000 for 1973-2005 (95% CI 0.04-0.04). There was a 1.66% overall increase in total cases diagnosed from 1975 to 2005 amounting to an annual increase of 2.21% (p value <0.05). There were 290 (61.4%) females and 182 (38.6%) males. Mean age at diagnosis was 68 (median 71; range 21-100). Patients above the age of 80 were more likely to be females (P = 0.03). 402 patients were white, 24 black, 45 other (American Indian/AK Native/Asian/Pacific Islander) and the rest were of unknown race. Stage of disease was localized in 34%, regional in 25%, distant in 25% and unstaged in 14%. Common sites were rectum (33%), anus and anal canal (26%), over lapping lesions of anorectum (21%) and esophagus (8%). While the rectum was the most common site in either gender (34% in each), 71.5% of anorectal melanomas were found in females while 68% of stomach and 71% of small intestinal melanomas presented in males (P = 0.0004). Significantly greater proportion of men (68 %) than women (43 %) were married while more women were widowed (37.5%) than men (7%) (P < 0.0001). 1-year and 5-year relative survival were 61% and 18% respectively (median survival 16 months). On univariate analysis, age and stage were significant variables with worst survival noted in age > 80 (P = 0.015) and distant disease (P < 0.0001). On multivariate analysis other race was prognostic of better survival (P = 0.02), while distant stage predicted worse survival (P = 0.01). There was no significant difference in survival based on site of tumor. Conclusion: While primary gastrointestinal melanoma continues to be rare, the incidence has steadily increased. Overall prognosis is poor and as in most malignancies, advanced age and stage of disease continue to be predictors of worse survival. Chances of survival may improve with earlier detection.