To provide a composition for an acoustic wave probe which can significantly improve the hardness and the mechanical strength (tensile strength at break, tensile elongation at break, tear strength, and abrasion resistance) of a silicone resin while maintaining a low acoustic attenuation, a silicone resin for an acoustic wave probe and the acoustic wave probe using the composition for an acoustic wave probe, an acoustic wave measurement apparatus, and an ultrasound diagnostic apparatus.To provide an ultrasound probe in which cMUT is used as an ultrasonic diagnostic transducer, and the composition for an acoustic wave probe and the silicone resin for an acoustic wave probe which can improve the sensitivity of the photoacoustic wave measurement apparatus and the ultrasound endoscope.Provided are a composition for an acoustic wave probe containing a polysiloxane mixture containing polysiloxane having a vinyl group, polysiloxane having two or more Si—H groups in a molecular chain, and one or more inorganic compound particles, in which the average primary particle diameter of the inorganic compound particles is less than 25 nm and the inorganic compound particles are selected from the group consisting of magnesium oxide, titanium oxide, iron oxide, zinc oxide, zirconium oxide, barium oxide, tin oxide, and ytterbium oxide; a silicone resin for an acoustic wave probe; an acoustic wave probe; an acoustic wave measurement apparatus; an ultrasound diagnostic apparatus; an ultrasound probe; a photoacoustic wave measurement apparatus; and an ultrasound endoscope.