PROBLEM TO BE SOLVED: To provide ultrasonic image diagnosis equipment which can shorten time required for the measurement and calculation of an optimum sonic velocity value and which can obtain an ultrasonic good-quality image of tissue or a lesion desired to be watched.SOLUTION: Ultrasonic image diagnosis equipment includes: an element data storage unit 22 for storing element data； a region-of-interest setting unit for setting a region of interest； an optimum sonic velocity calculation unit for calculating an optimum sonic velocity value of the region of interest by using the element data of the region of interest； a reconstruction region setting unit which includes the region of interest and which sets a reconstruction region wider than the region of interest； and an image reconstruction unit 24 for generating a reconstructed image by reconstructing an image in the reconstruction region, on the basis of the optimum sonic velocity value.【課題】最適音速値の測定・演算にかかる時間を短縮すると共に、見たい組織や病変の画質が良好な超音波画像を得ることができる超音波画像診断装置を提供する。【解決手段】素子データを記憶する素子データ記憶部２２と、着目領域を設定する着目領域設定部と、着目領域の素子データを用いて、着目領域の最適音速値を算出する最適音速算出部と、着目領域を含み、着目領域よりも広い再構築領域を設定する再構築領域設定部と、最適音速値に基づいて、再構築領域の画像を再構築して再構築画像を生成する画像再構築部２４とを有する。【選択図】図１
