&nbsp;Abstract&nbsp;Background: Latent adenocarcinoma of prostate refers to cases who present no obvious sign or symptom during their life spans and the tumor is incidentally found at postmortem examination. Its frequency can be very important in epidemiologic investigations, prevention and treatment. No previous study has been done in this regard in Iran and the studies performed in other countries show various results. The aim of present study is to determine the frequency of latent prostate carcinoma by studying the corpora of men above 50 years old referred to forensic medicine organization in Tehran in 2008 and 2009.&nbsp;Methods: In this study, 149 men aged above 50 who had died of different reasons and undergone autopsy were examined. Their prostates were excised and the slides were studied for the presence of adenocarcioma and prostatic intraepithelial neoplasia (PIN). In each case, age, weight of prostate, location of lesion, and grading according to Gleason's system were determined and the results were analyzed by SPSS software (version 16).&nbsp;Results: Out of 149 cases, 34(22.8%) had low grade PIN, 26(17.4%) high grade PIN, and 14(9.4%) invasive adenocarcinoma. Most of the tumors were located in posterior lobe of prostate and they were more frequent in older cases (>65 years of age) and heavier prostates (p value <0.05). All invasive adenocarciomas were accompanied by PIN.&nbsp;Conclusion: Worldwide studies show lower prevalence of latent carcinoma of prostate in Asian men than white European ones. Considering the absence of such studies in Iran, a larger study to compare and find out the precise rate of this kind of carcinoma, is recommended.&nbsp;