An acoustic lens (7) for an ultrasound transducer that is disposed in a front end portion of an ultrasound transducer (1) has a concave front surface (C1) and is formed from a base material (B) in which a plurality of fine particles (G) are dispersed. As a degree of dispersion of the fine particles (G) is higher from a central portion toward both end portions in an elevation direction, acoustic velocity is lower from the central portion toward both end portions in the elevation direction.