The pathogenesis of schizophrenia involves complex interactions between the environmental and genetic factors. Poly(ADP-ribose) polymerase-1 is activated in response to deoxyribonucleic acid damage. This study aimed to investigate the possible relationship between poly(ADP-ribose) polymerase-1 polymorphism and schizophrenia. The study included 320 participants, consisting of 140 individuals diagnosed with schizophrenia and 180 healthy controls. Haplotype analysis indicated that carrying the TT genotype for the rs7527192 polymorphism increased the risk of disease by 17 times compared to the CC genotype (odds ratio: 17.361, 95% confidence interval: 2.178-138.409, P < .0001). Individuals with the CT genotype had a 1.86-fold higher risk of developing schizophrenia than those with the CC genotype (P < .0001). Additionally, the T allele was found to increase the risk of schizophrenia by 2.09 times compared with the C allele (P < .0001). Identifying genetic risk factors in the etiology of schizophrenia may improve clinical follow-up and contribute to the treatment of this disorder.