An ultrasound observation apparatus includes: an agreement determination circuit configured to compare a reference image that is an ultrasound image chosen from ultrasound images and in which at least one region of interest is set and a latest ultrasound image with each other at least partly, and determine whether the reference image and the latest ultrasound image agree with each other； and a measurement circuit configured to, when the agreement determination circuit determines that the reference image and the latest ultrasound image agree with each other, transmit a push pulse to the at least one region of interest to cause shear waves, transmit and receive a tracking pulse to detect propagation of the shear waves, and measure elasticity characteristics in the at least one region of interest.
