Tobias Augustus Matthay (19 February 1858 – 15 December 1945) was an English pianist, teacher, and composer.
Matthay was born in Clapham, Surrey, in 1858 to parents who had come from northern Germany and eventually became naturalised British subjects. He studied composition at the Royal Academy of Music under Sir William Sterndale Bennett and Arthur Sullivan, and piano with William Dorrell and Walter Macfarren. He served as a sub-professor there from 1876-1880, and became an assistant professor of pianoforte in 1880, before being promoted to professor in 1884. With Frederick Corder and John Blackwood McEwen, he co-founded the Society of British Composers in 1905. Matthay remained at the RAM until 1925, when he was forced to resign because McEwen—his former student who was then the Academy's Principal—publicly attacked his teaching.