A single nuclear polymorphisms (SNPs) in the promoter region of the tumor necrosis factor-alpha (TNF-alpha) gene are involved in regulation of expression levels of TNF-alpha and therefore are associated with oncogenesis of several cancers. Aim of our study was to investigate the effect of G--->A polymorphism at -308 position in the promoter region of the TNF-alpha gene on prostate cancer (CalphaP) susceptibility in a subset of patients from Eastern Croatia. Study population consisted of 240 patients (120 with CalphaP, 120 controls). They were genotyped for TNF-alpha G-308A polymorphism using real-time PCR (LightCycler Instrument, Roche Diagnostics) and melting curve analysis method. X(2) test was used to compare distribution of TNF-alpha polymorphism genotypes between patients and control group. Relative risk was estimated by the odds ratio (OR). There was no significant statistical difference (X(2)=0.000, DF=1, p=1, OR=1, 95%CI=0.5537-1.8059) between patients and control group. Besides, data of CalphaP patients were stratified according to pathohistological diagnosis (PHD) by Gleason score and groups were compared according to TNF-alpha genotypes. Also, all patients and CalphaP patients were grouped according to prostate volume (V) into three groups: V<50 mL, V50-100 mL, V>100 mL. These groups were also compared according to TNF-alpha genotypes. There were no significant statistical differences between any of groups. Our findings suggest that TNF-alpha -308 SNP is not associated with CalphaP in Eastern Croatia population.