An ultrasonic image processing apparatus comprising: an inter-frame processor which applies a process between a first frame and a second frame acquired by transmitting and receiving ultrasound, and which calculates a movement destination on the second frame for each pixel of interest in the first frame, wherein each of the first and the second frame are formed with a plurality of beam lines before scan conversion and each beam line comprises a plurality of pixels; and a re-constructing unit which re-constructs the second frame into a higher spatial density frame using the movement destination calculated for each pixel of interest wherein the re-constructing unit re-constructs the higher spatial density frame by an interpolation process based on an original group of pixels of the second frame and an additional group of pixels defined by a pixel value of a pixel of interest in the first frame and a correspondent address with a fractional value for each pixel of interest wherein a correspondent address is a mapping address of a pixel of interest in the first frame on the second frame based on the movement destination of this pixel the correspondent address is a correspondent address with a fractional value, including an integer part corresponding to an integer multiple of an original pixel spacing in the second frame and a fractional value smaller than the original pixel spacing and wherein the higher spatial density frame comprises the plurality of beam lines of the second frame and a plurality of interpolation beam lines and each of the interpolation beam lines comprises a plurality of interpolation pixels generated by the interpolation process of pixel of the second frame and the additional group of pixels. an inter-frame processor which applies a process between a first frame and a second frame acquired by transmitting and receiving ultrasound, and which calculates a movement destination on the second frame for each pixel of interest in the first frame, wherein each of the first and the second frame are formed with a plurality of beam lines before scan conversion and each beam line comprises a plurality of pixels; and a re-constructing unit which re-constructs the second frame into a higher spatial density frame using the movement destination calculated for each pixel of interest wherein the re-constructing unit re-constructs the higher spatial density frame by an interpolation process based on an original group of pixels of the second frame and an additional group of pixels defined by a pixel value of a pixel of interest in the first frame and a correspondent address with a fractional value for each pixel of interest wherein a correspondent address is a mapping address of a pixel of interest in the first frame on the second frame based on the movement destination of this pixel the correspondent address is a correspondent address with a fractional value, including an integer part corresponding to an integer multiple of an original pixel spacing in the second frame and a fractional value smaller than the original pixel spacing and wherein the higher spatial density frame comprises the plurality of beam lines of the second frame and a plurality of interpolation beam lines and each of the interpolation beam lines comprises a plurality of interpolation pixels generated by the interpolation process of pixel of the second frame and the additional group of pixels.