ULTRASONIC FLOW METER

An ultrasonic flow meter comprises: a flow channel (3) through which the fluid to be measured passes; an ultrasonic transducer (5, 6) having an acoustic matching body (9c) mounted on a metal plate (9a) and a piezoelectric body (9b); an insulating damping member (11) that covers, excluding the acoustic matching body (9c), the metal plate (9a); a mounting portion (3b) provided in the flow channel (3); and a fixing member (13) to fix the ultrasonic transducer (5, 6) to the mounting portion (3b). The fixing member (13) has a pressing portion (18) and an extended portion (12). The ultrasonic transducer (5, 6) has a configuration so as to be fixed to the mounting portion (3b) by fitting a claw (15) provided on the mounting portion (3b) in a hole (16) provided on the extended portion (12). Thus, transmission in the case body can be reduced and precise ultrasonic flow measurement can be achieved.