PURPOSE: To provide a rotary disc system urine flow meter having excellent measurement accuracy.

CONSTITUTION: In the urine flow meter where a disc 1 is rotated by a motor 4 controlled so as to rotate at the fixed number of revolutions, and urine flow rate is measured by a load on the motor 4 when urination is carried out onto the disc 1 to fall clown the urine, a rotary body 8 which rotates in one body with the disc 1 and catches the urine scattering from the upper face of the disc 1 is attached to the periphery of the disc 1. The rotary body 8 is a doughnut-shaped. In addition, it is desirable to radially partition the inside of the rotary body 8 by a supporting body 9. The urine having been measured is discharged through the discharge path 12 of a cover body 11. The whole urine having fallen on the disc 1 is accumulated in the rotary body 8, and given the same speed as the rotary body 8. Thus, since the urine is given kinetic energy, it can be accurately measured.