The risk for sinonasal cancer associated with tobacco use was examined in a case-control study in males diagnosed between 1978 and 1981 in the Netherlands. Of the 116 cases of sinonasal cancer and 259 controls identified, interviews were completed for 92 (79%) of the cases and 195 (75%) of the controls. Ever-users of cigarettes had a moderately elevated risk for sinonasal cancer. The association was strongest for squamous cell carcinoma among recent users of tobacco (RR = 3.1, P less than 0.05, one-sided). For recent tobacco users, there was also a trend in risk associated with the amount of cigarette use (P less than 0.05, one-sided). Associations between tobacco use and adenocarcinoma were inconsistent, and no positive associations were found for the other histologic types, largely undifferentiated tumours. The study findings indicate that tobacco use, and in particular recent tobacco use, is associated with the development of squamous cell sinonasal cancer.