David S. King was born in Salt Lake City on 20 June 1917, the son of William H. King, United States Senator from Utah, and Vera Sjodahl. He attended public schools in Washington, D.C., and graduated from the University of Utah in 1937. Following a mission to Great Britain for the LDS Church from 1937 to 1939, he studied at Georgetown University School of Law, graduating in 1942. He was a law clerk to Justice Harold M. Stephens of the United States Court of Appeals for the District of Columbia in 1943.

After returning to Salt Lake City, King became counsel for the Utah State Tax Commission from 1944 through 1946. He established a private law practice in Salt Lake City in 1945, and between 1946 and 1958 also taught commercial law at Henager Business College.

Elected as a Democrat to the United States House of Representatives, he served from 1958 through 1962. He did not seek renomination to Congress in 1962, but was an unsuccessful candidate for election to the United States Senate from Utah in 1962. David King again won election to Congress in 1964, but was defeated for reelection in 1966.

King was appointed United States ambassador to the Malagasy Republic and to Mauritius in January 1967 and in May 1968, respectively, and served in those two positions concurrently until August 1969. From 1979 to 1981 he was alternate executive director of the World Bank.

He was called to serve as president of the Haiti Port-au-Prince Mission of the Church of Jesus Christ of Latter-day Saints from 1986 to 1989. David King has been married twice, first to Francine Evans and later to Rosalie Lehner. He is the father of five sons and two daughters.