Provided are an acoustic matching layer material including a thermosetting resin component and inorganic filler particles, in which in a cross-sectional observation of the acoustic matching layer material, a cross-sectional area of the inorganic filler particles satisfies Expression (1); an acoustic matching sheet; a composition for forming an acoustic matching sheet; an acoustic wave probe; an acoustic wave measurement apparatus; and manufacturing methods of an acoustic matching layer material and an acoustic wave probe:


100×b/c≥25  Expression (1)

wherein b: in a case where a number-average value of cross-sectional areas of the inorganic filler particles is denoted as a, a total cross-sectional area of particles having a cross-sectional area 7 times or more of a in the inorganic filler particles is denoted as b, and c: a total cross-sectional area of the inorganic filler particles is denoted as c.