The purpose of this study was to examine the distribution of prostate-specific antigen levels among Chinese,Malays and Indians in Singapore, taking the effect of age into consideration. The study was carried out as partof the Singapore Prostate Awareness Week from 23-26th February 2004. Men above 50 years old went to fourgovernment-restructured hospitals to participate in the study. Participants filled up a questionnaire and provided5 ml of blood for measurement of PSA levels using the Abbott IMx Total PSA assay (Abbott Laboratories).3,486 men responded to the study, comprising 92.8% Chinese, 3.0% Malays, 2.5% Indians and 1.8% Others.92.7% of them had PSA levels of 4 μg/L or less. There were no significant differences (p<0.05) between the meanPSA levels of Chinese (1.60 μg/L), Malays (1.39 μg/L), Indians (1.23 μg/L) and Others (1.70 μg/L). PSA levelswere significantly associated with age (Spearman’s r= 0.27, p<0.01). PSA levels increased with each 10-year agegroup and these trends were significant (p<0.0001) across both PSA group levels and age groupings. In the ≤50and >50-60 years age groups, the prevalence of PSA levels >4 μg/L were 1.1% and 3.7% respectively. This roserapidly to 11.3% and 23.5% for age groups >60-70 and >80 years respectively. Our study shows that the medianPSA levels in the Caucasian population in the USA are higher than those of Chinese, Malays and Indians inSingapore. PSA levels were positively associated with age. It may be more appropriate to offer PSA testing tomen who are >60 years old rather than the current >50 years.