The son of a musician in the royal band, Attwood was born in London. At the age of nine he became a chorister in the Chapel Royal. In 1783 he was sent to study abroad at the expense of the Prince of Wales (afterwards George IV), who had been favourably impressed by his skill at the harpsichord. After two years in Italy, Attwood proceeded to Vienna, where he became a favourite pupil of Mozart. On his return to London in 1787 he held for a short time an appointment as one of the chamber musicians to the Prince of Wales.
Soon after the institution of the Royal Academy of Music in 1823, Attwood was chosen to be one of the professors. He wrote the anthem O Lord, Grant the King a Long Life, which was performed at the coronation of William IV, and he was composing a similar work for the coronation of Queen Victoria hen he died March 24, 1838.
Attwood's funeral took place at St. Paul's Cathedral. He is buried in the Cathedral, in the crypt, under the organ.