William Louis DeAndrea (July 1, 1952 - October 9, 1996) was an American mystery writer and columnist.

During the 1980s his job took him to Europe, first to Paris and then London; on his return to the United States he settled in Litchfield County, Connecticut.

The Matt Cobb mysteries drew on DeAndrea's experience working for a major American television network.

In 1982, he participated in the intercontinental quiz show Top of the World, which pitted contestants via satellite from Australia, the US and the UK.

DeAndrea emerged as the American champion (thanks to his knowledge of Ellery Queen) and was invited to the final in London, but lost out to British insurance broker James Eccleson.