There is provided an ultrasound transducer device including a plurality of piezoelectric single-crystal plates that are stacked such that polarization components thereof are alternately inverted. The plurality of piezoelectric single-crystal plates are stacked such that directions thereof in which strain deformation in a direction orthogonal to a direction of voltage application from electrodes respectively interposed between the plurality of piezoelectric single-crystal plates becomes largest coincide with each other. There is also provided an ultrasound medical apparatus including the ultrasound transducer device.
