An ultrasound image diagnostic device including: a transducer to output transmission ultrasound toward a subject by a drive signal and also to output a reception signal by receiving reflection ultrasound from the subject a noise output section in which when the transducer receives the reflection ultrasound, a voltage containing noise is applied to the transducer to amplify the reception signal by a stochastic resonance phenomenon a harmonic extracting section to extract a harmonic component from the reception signal and an image processing section to generate ultrasound diagnostic image data of an interior of the subject based on the harmonic component extracted by the harmonic extracting section, wherein the noise output section applies a voltage containing noise such that the harmonic component is amplified by the stochastic resonance phenomenon to the transducer.
