To provide an ultrasonic flowmeter that prevents reduction in S/N ratio by suppressing the movement of a damping material applied to the pipe of the ultrasonic flowmeter, an ultrasonic flowmeter is provided. The ultrasonic flowmeter includes a first ultrasonic transceiver provided on a part of an outer periphery on an upstream side of a pipe in which gas flows, the first ultrasonic transceiver transmitting and receiving an ultrasonic wave, a second ultrasonic transceiver provided on a part of the outer periphery on a downstream side of the pipe, the second ultrasonic transceiver transmitting and receiving an ultrasonic wave, a main unit measuring a flow quantity of the gas, an ultrasonic absorber provided on the outer periphery of the pipe, the ultrasonic absorber including a first rubber layer formed on the outer periphery of the pipe and a second rubber layer formed on the first rubber layer.