Objective: To investigate lower urinary tract symptoms (LUTS) and their impact on quality of life (QOL) in patients having undergone renal transplantation (RTX). Methods: Forty-three patients (25 males and 18 females; age 20-68 years) undergoing RTX at Hokkaido University Hospital were included in this study. Median follow-up after RTX was 41 months (range 6-184). Pre-transplant dialysis had been carried out in 38 patients (median: 4.3 years, range: 1 month-31 years). All patients were assessed by uroflowmetry (UFM), postvoid residual urine volume (PVR), 24 h bladder diary, and International Prostate Symptom Score (IPSS). QOL score and King's Health Questionnaire (KHQ) were used for the assessment of LUTS-related QOL. Results: Mean fluid intake volume and urine output volume for 24 h were 2136 mL (1150-3430 mL) and 2446 mL (1336-4733 mL), respectively. Voiding dysfunction assessed by UFM and PVR was observed in 12 patients (28%) showing higher IPSS. QOL score and overall QOL in KHQ were not different between patients with and without voiding dysfunction. Although 19 (49%) had polyuria, 20 (51%) had nocturnal polyuria, which affected nocturia in IPSS as well as sleep/energy disturbances in KHQ compared with patients without nocturnal polyuria. Conclusions: Patients having RTX frequently present voiding dysfunction and nocturia basically caused by nocturnal polyuria. We should focus on LUTS in these patients to provide an appropriate management.