This paper overviewed risk factors of pancreatic cancer. Both genetic and environmental factors may be playingsignificant roles in the development of pancreatic cancer. Cigarette smoking has been established as a major riskfactor for pancreatic cancer, based on findings from almost all epidemiological studies. Long-term smoking cessationmay reduce the risk. The evidence that alcohol drinking and coffee consumption increase the risk is not sufficient,although an association with higher level of consumption remains a possibility. Diabetes mellitus, long-standingdiabetes in particular, may be a risk factor for pancreatic cancer. Individuals with hereditary pancreatitis or nonhereditarychronic pancreatitis are possibly at increased risk of pancreatic cancer. Higher intake of meat and fatmay be associated with an increased risk, while consumption of fruits/vegetables appears to have a protective effect.Individuals with mutations or deletion in such genes as K-ras, p16, p53, DPC4, and BRCA2 increased the risk ofdeveloping pancreatic cancer. Cigarette smoking may play a role in the development of these mutations.