The service of Thanksgiving drew about 2,000 admirers of the Australian-born soprano who died in Switzerland four months ago at the age of 83.
Prince Charles and former Prime Minister John Major were among those paying their respects to Sutherland, known as "La Stupenda" because of the purity of her voice
John Tooley, general director of the Royal Opera House for many years, praised Sutherland for her lasting impact on audiences throughout the world.
Sutherland first appeared at the Royal Opera House in 1952, but her international stature grew immeasurably after she made her Italian debut in the title role of Handel's "Alcina" in Venice in 1960.
"Joan was a superlative singer, possessed of a ravishingly beautiful voice: Pure, large, even throughout its wide range, flexible, warm and vibrant. She used it with consummate artistry to musical and dramatic ends," he said.
Despite her global fame, Tooley said, Sutherland remained a "supremely modest human being."
The service included music, prayers and readings. The Very Rev. John Hall, Dean of Westminster, presided, telling the congregation that Sutherland had "a voice like heaven" that captivated listeners for more than half a century.
The service was organized in part by the Australian High Commission. John Dauth, the high commissioner, said Sutherland had close ties to Britain despite her Australian birth.
"It's a great day to remember a great lady," he said. "A great Australian, but of course she pursued much of her career in this country. Those of us old enough to remember that extraordinary first performance of 'Lucia di Lammermoor' at the Royal Opera House in the late 1950s will forever treasure her in our hearts."