An ultrasound transducer includes: a tube； a transducer cable which is fixed to an end portion side of the tube and close to an outer periphery of the tube； a plurality of piezoelectric elements which are arranged along a circumferential direction surrounding a central axis of the tube to face an outer peripheral surface of the tube, each piezoelectric element being configured to output an ultrasound wave according to an electric signal input from the transducer cable, and convert an ultrasound wave input from an external portion into an electric signal； and a plurality of relays which are electrically connected respectively to a plurality of signal lines included in the transducer cable and the plurality of piezoelectric elements, the relays being configured to relay the plurality of signal lines and the plurality of piezoelectric elements.
