An ultrasound diagnostic apparatus and a method of producing an ultrasound image capable of accurately determining the boundary of an intima-media complex in an ultrasound image and measuring an intima-media thickness with high precision are provided. A candidate vascular wall boundary point determiner determines one or more candidate vascular wall boundary points based on a sound ray signal extending in a scanning direction in an ultrasound image. A boundary determiner determines a vascular wall boundary point from among the candidate vascular wall boundary points based on a third evaluation value and determines a vascular wall boundary, the third evaluation value being calculated based on a first evaluation value representing accuracy of each of the determined candidate vascular wall boundary points as a vascular wall boundary point and a second evaluation value representing similarity between the sound ray signal and the adjacent sound ray signal.