An ultrasound diagnostic apparatus includes: an ultrasound probe including an capacitive micromachined ultrasound transducer； an ultrasound observation apparatus to which the ultrasound probe is detachably connected, the ultrasound observation apparatus including a transmission circuit that generates an ultrasound transmission signal, and a reception circuit； a transmission ultrasound transducer and a reception ultrasound transducer included in the capacitive micromachined ultrasound transducer, the transmission ultrasound transducer including a plurality of transmission capacitive cells that each send ultrasound out, and the reception ultrasound transducer including a plurality of reception capacitive cells that each receive reflected ultrasound of the sent-out ultrasound and output an ultrasound reception signal； a transmission signal cable connecting the transmission ultrasound transducer and the transmission circuit； a reception signal cable connecting the reception ultrasound transducer and the reception circuit； a first matching section and a second matching section that perform electrical impedance matching for the ultrasound transmission signal and the ultrasound reception signal.
