Background: The aim of the study is to investigate differences in clinical presentation, disease stage and survival of operable pancreatic cancer patients with new onset DM compared to long standing diabetes mellitus (DM) and non diabetics. Methods: A prospectively maintained pancreatic cancer surgery database of a tertiary care teaching hospital from January 2006 to August 2012 was reviewed. Only patients with a histological diagnosis of pancreatic carcinoma (PC) were included in final analysis. DM was defined as HbA1c >6.5％ or any patient on anti-diabetic treatment regardless of HbA1c value. New onset DM was defined when diagnosed within two preceding years of surgery. Patients were stratified into two groups: DM and non DM. Among the DM patients, patients with new onset DM were further stratified and studied separately. Staging of PC was performed according to the 6th edition of AJCC. Survival of patients with PC was determined by reviewing medical records. Patients and their families were contacted if there was no existing follow-up. Results: Eighty-six patients (n=55, 63.9％ male) with a mean age of 62 years (range, 29-85 years) underwent pancreatic cancer surgery during the study period. Of the 86 patients, 30 (34％) had DM of which eight patients (9％ overall) had new onset DM. DM patients tended to be older compared to non DM patients (67.8 vs. 58.5 years, P=0.0005). The majority of non DM patients were symptomatic (98.2％), and there was a tendency for DM group patients to be asymptomatic at presentation (13.3％ vs. 1.8％, P=0.05). Abdominal pain was less common in DM patients compared to non DM patients (30％ vs. 53.6％, P=0.04). The median duration of new onset DM prior to diagnosis of PC was 2 months (range, 1-23 months). There was a tendency for DM patients to present at an early stage (stage I and stage II) (P=0.08). There was no difference in survival (P=0.17) for new onset DM compared to long standing DM and non DM patients. Conclusions: DM patients tend to be older and are less likely to present with abdominal pain. Asymptomatic presentation and early stage disease tends to occur in DM patients. A larger sample size is required to determine if survival of new onset DM patients differs from long standing and non DM patients.