[Objective] To investigate the impacts of voiding positions on urinary flow measurement (UFM) and post voided residual (PVR) in young males, to explore a better voiding position, and to provide reference for the clinical application of UFM. [Methods] A total of 43 male medical students (22-28 years old, all healthy with no lower urinary tract symptoms) from the First Affiliated Hospital of Xinxiang Medical College were enrolled.UFM was recorded in standing position, forward-bentding sitting position and sitting position, respectively.PVR was determined with B-ultrasound immediately after each voiding.Voided volume (VV), maximum urine flow rate (Qmax), average urine flow rate (Qave) and PVR were compared. [Results] In the standing, forward-bending sitting, and seating positions the VV were 211.6 (169.5, 265.9) mL, 206.8 (173.5, 262.8) mL, and 203.7 (175.9, 260.0) mL, respectively, with no significant difference (P=0.486); the Qmax were (26.00±2.33) mL/s, (26.41±2.12) mL/s, and (23.50±2.52) mL/s, respectively; the Qave were (14.03±2.21) mL/s, (14.27±2.18) mL/s, and (11.77±1.89) mL/s, respectively; the PVR were (9.97±2.26) mL, (9.43±1.97) mL and (12.10±3.28) mL, respectively.The Qmax and Qave in standing position and forward-bending sitting position were significantly higher than those in the sitting position, while the PVR was lower than that in the sitting position, with statistically significant difference (P<0.05). There were no significant differences in Qmax, Qave and PVR between the forward-bending sitting and standing positions (P>0.05). [Conclusion] Standing position and forward-bending seating position are beneficial for emptying the bladder, and these two positions are recommended for young men to urinate as the first choice.