Provided are an ultrasound diagnostic device and an elasticity analysis method whereby it is possible to analyze a region in an elasticity image which is suited to analysis. An ultrasound diagnostic device comprises: a tomographic image construction unit (24) which constructs a tomographic image of a diagnostic site of a subject via an ultrasound probe； an elasticity information computation unit (34) which computes elasticity information which denotes hardness； an elasticity image construction unit (36) which constructs an elasticity image on the basis of the elasticity information which is computed in the elasticity information computation unit (34)； an image display unit (28) which displays the tomographic image and the elasticity image； an analysis region detection unit (50) which detects an analysis region, wherein the elasticity information is analyzed, from distribution information of the elasticity information which constructs the elasticity image； and an analysis unit (52) which analyzes the elasticity information corresponding to the analysis region.
