Objectives: To find out the efficacy of multi-parametric MRI as a noninvasive diagnostic investigation in carcinoma prostate and its correlation with Gleason scoring among men with PSA levels between 4 to 10 ng/ml and with normal digital rectal examination. Methods: A prospective study was done in Institute of Urology, MMC, Chennai between September 2015 to April 2016. 25 male patients who presented with obstructive LUTS with PSA 4-10 ng/ml and a normal DRE were included in the study. Patients with active UTI, prostatitis, initial presentation as AUR, nodular prostate on DRE, claustrophobia or metal implants were excluded from study. All patients were subjected to 13 core TRUS guided biopsy and multi-parametricMRI. Results: The age of the patients in the current study ranged from 51 to 81 years, with a mean age of 66.76 ± 7.8 years. 9 patients (36%) were positive for malignancy in multi-parametric MRI while 8 patients (32%) were positive for malignancy in TRUS biopsy. The multi-parametric MRI based PIRADS score had a sensitivity of around 100% and a specificity of 94.12% compared to the TRUS biopsy. According to the classification of multi-parametric-MRI based PIRADS score, about 24% of the patients had highly suspicious malignancy and about 12% had a probably malignant lesion while 16% of the patients had indeterminate lesions. There was also a positive linear correlation between PIRADS score & Gleason score and also PIRADS score &PSA levels. Conclusion: Based on the findings of this study, it can be concluded that multi-parametric MRI of prostate for patients with grey zone PSA and normal DRE is an invaluable, non-invasive and feasible option to detect carcinoma prostate with a high sensitivity and specificity besides high predictive values and can help in identifying patients in need of biopsy. It can be also helpful in performing targeted biopsy and in characterizing the extent &aggressiveness of the prostate cancer.