Polymorphisms in glutathione S-transferase (GST) genes may influence response to oxidative stress and modify prostate cancer (PCA) susceptibility. These enzymes generallydetoxify endogenous and exogenous agents, but also participate in the activation and inactivation of oxidative metabolites that may contribute to PCA development. Several studies show some differences in association of glutathione S-transferase M1 and T1 genetic polymorphisms with the risk of prostate cancer in various populations. The current study was done with Iraqi patient to evaluate the association of the polymorphism of glutathione S-transferase subtypes (T, M) and the susceptibility of prostate cancer in Iraqi patients as compared to controls. Blood samples were collected from 35 prostate cancer patients and 25 health individuals as controls from Ghazi Al-hariri hospital, Baghdad, Iraq. The multiplex polymerase chain reaction PCRmethod was used to determine the polymorphism of the glutathione S-transferase theta (GSTT) 1 and glutathione S-transferase mμ (GSTM) 1 null allele. There was significant association in the GSTM1 gene polymorphism and prostate cancer risk (P<0.05). Moreover, significant relationship was found between the polymorphism of GSTT1 genes and higher risk of prostate cancer among Iraqi subjects (P<0.05). This study showed that polymorphism of GSTT1 and GSTM1 genes can be predisposing risk factors for prostate cancer among Iraqi subjects.