Background The purpose of this investigation was to evaluate the relation between employment in motor vehicle manufacturing (MVM) and fatal prostate cancer. Methods The study included 322 prostate cancer deaths occurring in 1973 through 1987 and 1,285 controls, selected from a cohort of 126,100 male MVM workers. Results Men employed in casting operations had an odds ratio of 1.5 (95% CI 1.1ยฑ 2.0). The association was consistent across casting facilities and was attributable primarily to work in core and mold making (OR 1.5, 95% CI 1.1ยฑ2.2) and metal melting and pouring jobs (OR 1.9, 95% CI 1.0ยฑ3.6). Other results included ORs of 1.9 (95% CI 1.0ยฑ3.7) for warehousing and distribution operations and 2.1 (95% CI 1.2ยฑ3.7) for electric and electronic equipment manufacturing. The latter two associations exhibited little internal consistency. Conclusions The relationships seen in this study were weak and may have been due to chance. Core and mold making and metal melting and pouring foundry operations entail potential exposure to metal dusts and fumes, to polycyclic aromatic hydrocarbons (PAHs), and to other chemicals. However, associations between these exposures and prostate cancer have not been reported consistently, nor have other studies of foundry workers consistently noted an excess of prostate cancer.