An ultrasonic diagnostic apparatus based on performing constant false alarm rate (CFAR) processing, comprising: an ultrasonic wave transmitting/receiving unit (21, 22) adapted to transmit an ultrasonic wave to a subject, to receive a reflected wave of the ultrasonic wave, and to generate echo signals corresponding to a first cross section and second cross sections on the basis of the received reflected wave, the second cross sections being positioned at both sides of the first cross section in a direction that is substantially orthogonal to the first cross section; an image data generating unit adapted to generate a plurality of two-dimensional images corresponding to the first cross-section and the second cross-sections on the basis of the echo signals and to generate three-dimensional image data composed of the plurality of two-dimensional images; an image generating unit adapted to generate a first image corresponding to the first cross section by performing a process of enhancing a microstructure by using the plurality of two-dimensional images; and a display unit adapted to display the first image, wherein the process of enhancing the microstructure included in the three-dimensional image data is signal processing of reducing a speckle pattern component included in the three-dimensional image data, wherein the signal processing of reducing the speckle pattern component is a CFAR (constant false alarm rate) processing where a kernel pattern of adjacent pixels of an interesting pixel is three-dimensionally defined, and the CFAR processing is performed for all the interesting pixels P i by the following processes (a) to (c): (a) First, the average value of the brightnesses of the adjacent pixels of each interesting pixel P i is calculated. (b) Then, a value obtained by subtracting the average value from the pixel value of the interesting pixel P i is defined as a calculation result K i for the position of the interesting pixel P i, and the value is stored in an internal storage unit. (c) Then, when a predetermined threshold value is T and K i ≥T is satisfied, the original brightness is used to display the interesting pixel P i, and when K i < T, the brightness value of the interesting pixel P i becomes zero, and the interesting pixel is not displayed. an ultrasonic wave transmitting/receiving unit (21, 22) adapted to transmit an ultrasonic wave to a subject, to receive a reflected wave of the ultrasonic wave, and to generate echo signals corresponding to a first cross section and second cross sections on the basis of the received reflected wave, the second cross sections being positioned at both sides of the first cross section in a direction that is substantially orthogonal to the first cross section; an image data generating unit adapted to generate a plurality of two-dimensional images corresponding to the first cross-section and the second cross-sections on the basis of the echo signals and to generate three-dimensional image data composed of the plurality of two-dimensional images; an image generating unit adapted to generate a first image corresponding to the first cross section by performing a process of enhancing a microstructure by using the plurality of two-dimensional images; and a display unit adapted to display the first image, wherein the process of enhancing the microstructure included in the three-dimensional image data is signal processing of reducing a speckle pattern component included in the three-dimensional image data, wherein the signal processing of reducing the speckle pattern component is a CFAR (constant false alarm rate) processing where a kernel pattern of adjacent pixels of an interesting pixel is three-dimensionally defined, and the CFAR processing is performed for all the interesting pixels P i by the following processes (a) to (c): (a) First, the average value of the brightnesses of the adjacent pixels of each interesting pixel P i is calculated. (b) Then, a value obtained by subtracting the average value from the pixel value of the interesting pixel P i is defined as a calculation result K i for the position of the interesting pixel P i, and the value is stored in an internal storage unit. (c) Then, when a predetermined threshold value is T and K i ≥T is satisfied, the original brightness is used to display the interesting pixel P i, and when K i < T, the brightness value of the interesting pixel P i becomes zero, and the interesting pixel is not displayed. (a) First, the average value of the brightnesses of the adjacent pixels of each interesting pixel P i is calculated. (b) Then, a value obtained by subtracting the average value from the pixel value of the interesting pixel P i is defined as a calculation result K i for the position of the interesting pixel P i, and the value is stored in an internal storage unit. (c) Then, when a predetermined threshold value is T and K i ≥T is satisfied, the original brightness is used to display the interesting pixel P i, and when K i < T, the brightness value of the interesting pixel P i becomes zero, and the interesting pixel is not displayed.