OBJECTIVE:To estimate the burden of pancreatic cancer in Australia attributable to modifiable exposures, particularly smoking. DESIGN:Prospective pooled cohort study. SETTING, PARTICIPANTS:Seven prospective Australian study cohorts (total sample size, 365 084 adults); participant data linked to national registries to identify cases of pancreatic cancer and deaths. MAIN OUTCOME MEASURES:Associations between exposures and incidence of pancreatic cancer, estimated in a proportional hazards model, adjusted for age, sex, study, and other exposures; future burden of pancreatic cancer avoidable by changes in exposure estimated as population attributable fractions (PAFs) for whole population and for specific population subgroups with a method accounting for competing risk of death. RESULTS:There were 604 incident cases of pancreatic cancer during the first 10 years of follow-up. Current and recent smoking explained 21.7% (95% CI, 13.8-28.9%) and current smoking alone explained 15.3% (95% CI, 8.6-22.6%) of future pancreatic cancer burden. This proportion of the burden would be avoidable over 25 years were current smokers to quit and there were no new smokers. The burden attributable to current smoking is greater for men (23.9%; 95% CI, 13.3-33.3%) than for women (7.2%; 95% CI, -0.4% to 14.2%; P = 0.007) and for those under 65 (19.0%; 95% CI, 8.1-28.6%) than for older people (6.6%; 95% CI, 1.9-11.1%; P = 0.030). There were no independent relationships between body mass index or alcohol consumption and pancreatic cancer. CONCLUSIONS:Strategies that reduce the uptake of smoking and encourage current smokers to quit could substantially reduce the future incidence of pancreatic cancer in Australia, particularly among men.