Disclosed is a uroflowmeter attachable to a toilet capable of diagnosing a BPH with high reliability and convenience in a sanitary way without the constraints of a space by checking the urinary flow rate of a patient. The uroflowmeter includes a toilet bowl for temporarily storing feces and urine, a connection tube which has one end introduced into water of the toilet bowl, a pressure measuring unit connected with an opposite end of the connection tube to measure pressure inside the toilet bowl, a signal analyzing unit for analyzing pressure signals from the pressure measuring unit to measure a urinary volume signal and a urinary flow rate signal, a display unit for displaying the urinary flow rate signal measured by the signal analyzing unit, and a wireless transceiver unit for making data communication with the signal analyzing unit in a wireless way.