The Prostate Specific Antigen (PSA) is the best and most commonly used tumor maker for prostate in clinical practice these days ^(1,2). It is a glycoprotein has molecular weight of 33KD. PSA is very routinely used in the diagnosis and follow up of prostate disease, specially prostate cancer ^(3,4). Prostate Specific Antigen (PSA) is formed in two different molecular types in serum; they are free PSA (fPSA) and complex PSA (cPSA), the serum of which form the total PSA (tPSA).fPSA is mostly used in the detection of Prostate cancer ⁽⁵⁾. Free PSA 28 kda is eliminated by glomerular filtration. The date revealed that the patients with end stage of renal dysfunction prolonged dialysis with increase percent of fPSA ^{(6,7, 8, 9)}.