An ultrasound image-generating apparatus (10), which reduces the directional dependence of the accuracy of acquiring ultrasound probe position, is equipped with: a first movement-estimating unit (10A) that estimates movement vectors, which represent the movement of the ultrasound probe when multiple images corresponding respectively to multiple ultrasound signals were acquired, as first movement vectors by a first estimating method a second movement-estimating unit (10B) that estimates the movement vectors, when the multiple images corresponding respectively to the multiple ultrasound signals were acquired, as second movement vectors by a second estimating method with a different directional dependence of estimating accuracy from the first estimating method and a position-reconstructing unit (10C) that calculates combined movement vectors by a weighted combination of the first movement vectors estimated by the first movement-estimating unit (10A) and the second movement vectors estimated by the second movement-estimating unit (10B) based on the direction of the first movement vector or the second movement vector and constructs ultrasound diagnostic images of the subject using the combined movement vectors and the multiple images.Linvention concerne un appareil de génération dimages par ultrasons (10), qui réduit la dépendance directionnelle de la précision dacquisition de la position de la sonde à ultrasons, qui comprend : une première unité destimation de mouvement (10A) qui estime les vecteurs de mouvement, qui représentent le déplacement de la sonde à ultrasons quand plusieurs images correspondant respectivement à plusieurs signaux ultrasons ont été acquises, en tant que premiers vecteurs de mouvement par un premier procédé destimation une seconde unité destimation de mouvement (10B) qui estime les vecteurs de mouvement, quand plusieurs images correspondant respectivement à plusieurs signaux ultrasons ont été acquises, en tant que seconds vecteurs de mouvement p
