A method and system for measuring a urinary flow rate minimizes impact noise caused by urine to measure the urinary flow rate using a plurality of load cells when prostatic hypertrophy is diagnosed. The method includes measuring an amount of urine collected into a container using a plurality of load cells, extracting and averaging urinary flow rate signals from the measured results, and removing the impact noise from the urinary flow rate signals, converting the urinary flow rate signals into digital signals through an A/D converting circuit, and outputting the digital signals using a personal computer or a microprocessor analyzer which is interfaced with the A/D converting circuit.