OBJECTIVE: To reinvestigate whether South Asian men in the UK are at lower risk of being diagnosed with prostate cancer in a UK-based retrospective cohort study and to examine possible reasons that may explain this. PATIENTS AND METHODS: The catchment areas were predefined in four areas of southern England, and age- and race-specific populations for those areas taken from census data. Cases were ascertained through review of multiple hospital sources, while race, other demographic factors, and medical history were determined using questionnaires sent to the men, hospital records review and death certificates. The South Asian group included men of Indian, Bangladeshi and Pakistani origin. RESULTS: There was modest evidence of lower prostate cancer rates in South Asian men compared with their White neighbours (age-adjusted rate ratio 0.81; 95% confidence interval 0.65-1.00). This difference did not reflect less use of prostate-specific antigen (PSA) testing or differences in clinical features at presentation. CONCLUSION: This study provides evidence of a lower incidence of prostate cancer amongst South Asian men living in England, in comparison with their White counterparts. If anything, South Asian men presented with clinical features of earlier disease suggesting that the reduced risk is unlikely to be an artefact of poorer access to health care.