Objectives: Periampullary carcinoma is a term widely used to define a heterogenous group of neoplasms arising from the head of the pancreas, ampulla of Vater, terminal common bile duct and the duodenum. Periampullary carcinomas typically have either the intestinal type or pancreatobiliary type of the differentiation. The prognostic importance of the type of differentiation is studied in relation to the other prognostic factors like resection margin involvement, tumour size, nodal involvement, vascular infiltration, perineural growth and degree of differentiation. Methods: 50 whipples resected specimens were analyzed. In these cases 33 were periampullary carcinomas and the remaining were chronic pancreatitis. The clinical features, laboratory investigations and histopathological features of periampullary carcinomas were studied. Prognostic factors were studied in two histological types of periampullary carcinomas i.e. intestinal type and pancreatobiliary type. Results: Out of 33 periampullary carcinomas 24 were intestinal type and 9 were pancreatobiliary type. Periampullary carcinomas were common in females (54.5%) and were seen mostly in the age above 60yrs (36.4%). Jaundice was the most common presenting symptom. Independent adverse prognostic factors seen in the pancreatobiliary type of differentiation were tumor size more than 2.5cm (66.7%), tumor stage, regional lymphnode involvement (77.8 %), vessel involvement (55.6%), perineural growth, areas with poor differentiation (66.7%) and serum CA19-9 levels more than 200U/ml (77.8%). Conclusion: In periampullary carcinomas histological type of differentiation is very important independent prognostic factor. In the two histological types of carcinomas pancreatobiliary has worse prognosis when compared to intestinal type.