An ultrasonic probe apparatus comprising: an ultrasonic transducer configured to output an electrical signal upon receiving ultrasonic waves; a sound absorption unit, including a sound absorption material for absorbing sound, with one surface on which the ultrasonic transducer is installed, and being electrically connected to the ultrasonic transducer; a first electronic circuit electrically connected to the sound absorption unit; and a second electronic circuit, the ultrasonic probe apparatus being characterized in that the second electronic circuit is disposed between a surface of the sound absorption unit opposite to the surface on which the ultrasonic transducer is installed and the first electronic circuit, and is configured to electrically interconnect the first electronic circuit and the sound absorption unit, wherein one surface of the second electronic circuit faces the sound absorption unit, and the other surface of the second electronic circuit faces the first electronic circuit, wherein the sound absorption unit includes at least one first connection unit electrically connected to the ultrasonic transducer, and wherein the second electronic circuit includes: an output unit configured to output a signal processed by the first electronic circuit; a first substrate connection unit provided to pass through from the one surface of the second electronic circuit to the other surface of the second electronic circuit, provided at a position in contact with the first connection unit, and configured to electrically interconnect the sound absorption unit and the first electronic circuit; and a second substrate connection unit provided at a position not in contact with the first connection unit of the sound absorption unit, and configured to electrically interconnect the first electronic circuit and the output unit. an ultrasonic transducer configured to output an electrical signal upon receiving ultrasonic waves; a sound absorption unit, including a sound absorption material for absorbing sound, with one surface on which the ultrasonic transducer is installed, and being electrically connected to the ultrasonic transducer; a first electronic circuit electrically connected to the sound absorption unit; and a second electronic circuit, the ultrasonic probe apparatus being characterized in that the second electronic circuit is disposed between a surface of the sound absorption unit opposite to the surface on which the ultrasonic transducer is installed and the first electronic circuit, and is configured to electrically interconnect the first electronic circuit and the sound absorption unit, wherein one surface of the second electronic circuit faces the sound absorption unit, and the other surface of the second electronic circuit faces the first electronic circuit, wherein the sound absorption unit includes at least one first connection unit electrically connected to the ultrasonic transducer, and wherein the second electronic circuit includes: an output unit configured to output a signal processed by the first electronic circuit; a first substrate connection unit provided to pass through from the one surface of the second electronic circuit to the other surface of the second electronic circuit, provided at a position in contact with the first connection unit, and configured to electrically interconnect the sound absorption unit and the first electronic circuit; and a second substrate connection unit provided at a position not in contact with the first connection unit of the sound absorption unit, and configured to electrically interconnect the first electronic circuit and the output unit. an output unit configured to output a signal processed by the first electronic circuit; a first substrate connection unit provided to pass through from the one surface of the second electronic circuit to the other surface of the second electronic circuit, provided at a position in contact with the first connection unit, and configured to electrically interconnect the sound absorption unit and the first electronic circuit; and a second substrate connection unit provided at a position not in contact with the first connection unit of the sound absorption unit, and configured to electrically interconnect the first electronic circuit and the output unit.