To test the hypothesis that RC priests are at low risk for prostatic cancer because of their celibacy, a cohort of 10,026 men who were active or retired diocesan RC priests in the US on 1/1/49 were followed until death, leaving the priesthood or 1/1/78. The overall standardized mortality ratio (SMR) was 103 & the SMR for cancer of the prostate was 81. Other findings include increased SMR’s for cancer of the larnyx, cirrhosis & diabetes & decreased SMR’s for lung cancer, emphysema & suicide.