Cancer incidence between 1971 and 1994 was studied in a cohort of 7,512 men and 1,942 women who had been employed for at least 3 months in a Finnish enterprise that was primarily active in oil refining. The expected numbers of cancer cases were based on the national incidence rates. The standardized incidence ratios (SIR) for overall cancer after 5 years at work was decreased by 12% because of a significant deficit from cancer of the lung in oil refineries (SIR, 0.3; 95% confidence interval [95% CI], 0.1-0.6). There was a significant excess of kidney cancer in males, which was highest among men with at least 5 years of employment in oil refineries (SIR 2.8; 95% CI, 1.6-4.7). Male blue-collar workers had a twofold risk of non-Hodgkin's lymphoma and non-melanocytic skin cancer. Occupational exposure to gasoline may be associated with increased risk of cancer of the kidney.