A multi-institute, hospital-based, case-control study on pancreatic cancer was carried out to examine its association with preceding diseases, cigarette smoking, alcohol drinking and dietary factors. Analyses were based on 124 newly diagnosed exocrine pancreatic cancer cases and sex-, age- and institute-matched hospital controls in seven hospitals in Japan. Cigarette smoking showed a positive association with the risk of developing pancreatic cancer. Especially among smokers, a risk enhancing effect of involuntary/passive smoking prior to twenty years of age was observed (P < 0.05). No consistent associations were found with coffee, black tea or alcohol consumption. Among dietary factors, favoring food of a salty taste and drinking green tea five cups per day or more were positively associated with the risk. Drinking milk and eating fish everyday were inversely associated with the risk.