Sir William Henry Harris (28 March 1883 - 6 September 1973) was an English organist and composer, affectionately nicknamed 'Doc H' by his choristers.

Harris was born in Fulham, London and died in Petersfield. He was a chorister of Holy Trinity, Tulse Hill. At the age of 14, he took up a "flexible" position as Assistant Organist at St David's Cathedral in Wales, followed at 16 by a scholarship to the Royal College of Music where he was Professor of Organ and Harmony from 1921 to 1955. He was organist at St Augustine's Church, Edgbaston from 1911 to 1919 and concurrently of Assistant Organist at Lichfield Cathedral followed in 1919 by becoming Organist successively at New College and in 1929 Christ Church, Oxford, moving to St. George's Chapel, Windsor in 1933.

As Organist at Windsor, Harris was at his most productive. He produced music for the Three Choirs Festival, was a conductor at both the 1937 and 1953 coronations, and had music premiered at the Proms, all of which led to being awarded his KCVO in 1954.

Harris is best remembered for his Anglican church music, though his main achievements were as a choir-trainer. His most famous works are the anthems Faire is the heaven (1925) and to a lesser extent Bring us, O Lord God (1959), both for unaccompanied double choir, and Strengthen ye the weak hands (1949) for choir and organ. His very accessible Communion Service in F was frequently sung in a great many Anglican parish churches up until the 1970s. The canticles Harris in A and Harris in A minor are still sung at Evensong in a number of Anglican cathedrals. He also composed cantatas and organ pieces, as well as the hymn tune Alberta (often used for the words Lead, Kindly Light), and various Anglican psalm chants.