Born in Cardiff, Wales, as David Ivor Davies. Novello also wrote under the names David L'Estrange and H.E.S. Davidson. His mother was the singer Dame Clara Novello Davies. His father, David Davies was a tax collector.
With a fine soprano voice he won a scholarship to Magdalen Choir School, Oxford, where he was a chorister. While at school he began to write songs under the name Ivor Novello and some were published and became popular. He came to be known as "the Welsh Prodigy".
Soon after Ivor Novello had left school he and his parents moved to London and lived at 55 New Bond Street from 1910 to 1913. A singing coach was arranged for him. He then lived in a flat at 11 Aldwych, above the Strand Theatre, from 1913 to 1951.
In 1914 he wrote the song Keep the Home Fires Burning which became the most popular song amongst British soldiers. This led to him being asked to write the music for several West End productions, including Theodore and Co. which ran at the Gaiety Theatre for eighteen months.
In December 1915 he was introduced to the patron of the arts, Edward Marsh, and they remained friends for twenty years. Ivor Novello went round to Edward Marsh's flat to compose on his piano.
In 1916 he met the 21-year-old actor Robert (Bobbie) Andrews. They became friends and lovers and were together for 35 years. They appeared together in many of Ivor Novello's plays and musicals.
On the way back from a holiday with Bobby Andrews in New York after WWI, Ivor Novello received a cable offering him a starring role in the silent film The Call of the Blood (1919). It was a great success and Ivor Novello was called "the New Valentino" and "the British Adonis". He did many more silent films, and later on had more success in talkies.
In 1924 he wrote his first play in collaboration with the actor Constance Collier. Ivor Novello starred in the play, and then again in the film that followed.
In 1935 he wrote and starred in the musical play Glamorous Night for Drury Lane. This was the first of a series musical plays which filled the Drury Lane theatre for a number of years.
The flat in Aldwych attracted many people from the theatre and literature including J. R. Ackerley, Noël Coward, Jack Buchanan, Gertrude Lawrence, Edward Marsh, Somerset Maugham, Paul Robeson, and Siegfried Sassoon.
In 1944 Ivor Novello went to prison at Wormwood Scrubs for four weeks of an eight-week sentence for the misuse of petrol coupons - the judge notoriously loathed homosexuals. He had taken up a fan's suggestion of using a Rolls Royce.
He then travelled with ENSA to entertain the troops in France and Belgium. His song We'll Gather Lilacs became very popular. It was incorporated later into a musical play.
He bought a house in Jamaica where he and Bobby Andrews went on holiday together. Bobby Andrews was with Ivor Novello when he callapsed in his flat in London in the early hours of the morning and died of a coronary thrombosis.