Aim: To evaluate the association of PSA serum level and Gleason score with PNI in prostate cancer subjects. Material and methods: 50 prostatic resection TURP (Transurethral Resection of Prostate) samples presenting to the Department of Pathology were diagnosed and also confirmed to have carcinoma prostate were included in the study.Thorough detailed history including supportive investigations was recorded for all the patients on a proforma.Record of any investigations like PSA level, USG, CT and bone scan findings was also recorded.All specimens were routinely processed and stained with Hematoxylin and Eosin (H & E stain).Gleason score along with presence or absence of peri-neural invasion was assessed in each considered case. Results: There was a statistically significantpositive correlation between increasingmean serum PSA levels and Gleason score. The correlation between PSA (ng ml−1) and Gleason score was statistically significant (p value<0.01). The mean PSA (ng ml−1) in cases with Perineural Invasion was 56.39±19.48 and in subjects in whom Perineural Invasion was absent mean PSA (ng ml−1) was 8.02±5.59. Conclusion: This study concluded that in patients with prostatic adenocarcinoma, there was a statistically significantpositive correlation between increasingmean serum PSA levels and Gleason scoreof prostatic carcinoma. The mean level of PSA was statistically significant correlated with presence of perineural invasion. Based on findings of the current study, Gleason score isa prognostic factor of PNI among casesundergone prostate biopsy.