Background: Benign prostatic enlargement (BPE) is the most common prostatic condition affecting middle-aged and elderly men1, 2. It is the most common cause of bladder outlet obstruction (BOO) in men3. Significant postvoid residual urine volume (PVR) is a common finding in patients with bladder outlet obstruction (BOO) secondary to BPE4, 5. Urologists traditionally use increasing amounts of PVR to connote BPE progression and thus an "indication" for treatment. Accurate determination of PVR is therefore of paramount importance in urologic practice and it serves as an index of adequacy of bladder emptying. There are few but conflicting studies comparing ultrasound and urethral catheter measurements of PVR in patients with BPE and therefore studies to determine the reliability of USS in accurate measurement of PVR is still desired. Aim: This study aimed to compare the use of USS with urethral catheterization for PVR measurement in patients with BPE in Ile-Ife. Methodology: This was a prospective, comparative, hospital-based study. Consecutive, consenting, Nigerian men with symptomatic BPE who presented to the urology out-patient clinic of OAUTHC, Ile-Ife, were recruited for the study. They had prostate volume and bladder wall thickness measured by ultrasound. They also had PVR measured by both ultrasound and urethral catheterization methods. The data obtained were entered into a proforma and analyzed using SPSS version 22. Results: Forty-six patients completed the study. Their actual median PVR (urethral catheter measured) was 106.5ml (range 26-480ml), the median ultrasound measured PVR was 103.5ml (range 32-431.4ml). There was a near perfect positive correlation between the actual PVR and utrasound measured PVR (r = 0.976, p<0.01). The median prostate volume was 100.00ml (range 30.2-388ml) while the mean BWT was 5.19±1.8mm. The actual PVR positively correlated with PV (0.648, p<0.01) and BWT (r=0.459, p<0.01). Conclusion: This study showed a near perfect positive correlation between the actual PVR and ultrasound measured PVR of patients with benign prostate enlargement. Keywords: prostate, postvoid residual, ultrasound scan, catheterization, bladder wall thickness