Background: The enlargement of prostate is known as benign prostatic hypertrophy (BPH). It begins when the cells of the prostate gland begin to proliferate. BPH is caused by increased age and other factors associated with it. Objective: To determine the correlation of prostate volume with age and post-micturating residual (PMR) volume in patients with benign prostatic hyperplasia (BPH). Methods: This cross-sectional study was conducted on 100 patients of BPH that fulfilling inclusion criteria for 4 months, selected from Gondal Medical Complex Gujranwala during 14 January to 15 May 2022. Patients with prostate cancer, mild urinary tract or prostate surgery, and those with UTI or stone in bladder were excluded. Ultrasound was used to perform a transabdominal scan. Age, prostate volume (PV), and PMRV were the outcome parameters. Results: In this study hundred BPH positive patients were included. The mean age of patients with BPH, prostate weight, post-void residual volume of the participants was found to be 64.89±14.12 years, 54.68±29.42g, and 22.47±14.75ml respectively. In this study the correlation value of age of patients with BPH and prostate volume was 0.212 and P-value was 0.035 which was significant but the correlation between PV and PMRV was not significant because the correlation value of PV and PMRV was 0.032 and P-value was 0.751. Conclusion: This study concluded that there was significant correlation between Age and BPH but no significant correlation between BPH and PMRV.