Iranian tissue bank prepares a wide range of human tissue grafts such as; heart valve, bone, skin and amniotic membrane for different clinical applications. Upon AATB standards the donor’s blood sample is tested for: HIV1,2 Antibody, HBsAg, HBcAb, HCV Ab, HTLV1,2Ab and RPR. The availability of tissue allograft is often limited by these viruses. The purpose of this retrospective review was to determine the human tissue allograft discard rates related positive serological tests. From April 2002 to April 2007,1548 tissue donors including 56 amniotic membrane living donors and 1492 bone, heart valve, skin and other tissues cadaver donors(1171 males and 377 females)were screened and procured after informed consent had been obtained. All donors were reviewed for the cause of death, past medical history, physical examination and social history and donors’ blood sample were tested with serological methods. 181donors (11.69 %) were discarded due to positive serology. HBcAb was the most predominant reason (5.55 %) that followed by HBsAg (2.9 %) and then HCV Ab (2.84 %), HTLV1,2Ab (1.61 %), HIV1,2Ab (0.64 %), and RPR (0.51 %) was the least predominant. We found a significant correlation between donor’s sex and positive serology (males> females, P value< 0.05). In conclusion, despite the strict adherence to donor selection criteria, positive serology in blood sample of tissue donors does not reach zero and we need better screening methods in order to decrease our current discard rates and cost of procured tissues. We recommend that all tissue banks should be involve both routine serological procedures and other complementary tests such as; NAT for screening of tissue donors and increasing tissue safety and assurance. The addition of NAT to screening of tissue donors can reduce the risk of transmission of viral infections from donor to recipient for providing safe allograft tissues.