William Hoover Yawkey (August 22, 1875 – March 5, 1919) was an American business executive in the lumber and mining industries.^[1] He was the sole owner of the Detroit Tigers of the American League from 1903 through 1908, and majority owner from 1908 to 1919.^[2]

Yawkey was the son of wealthy Michigan lumber tycoon William Clyman Yawkey.^[3] The elder Yawkey agreed to buy the Tigers from Samuel F. Angus in 1903, but died before the deal closed.^[2] Frank Navin, then the Tigers' bookkeeper and vice president, persuaded the younger Yawkey to complete the deal.^[4]

Yawkey took little interest in the Tigers, leaving day-to-day control in Navin's hands.^[2] In 1908, Yawkey sold almost half of the club's stock to Navin, effectively making Navin a full partner.^[2] Yawkey died in Augusta, Georgia, in 1919 from the Spanish flu. He was interred in a family lot in Brattleboro, Vermont.^{[5][lower-alpha 1]} Following Yawkey's death, Navin bought additional stock from the Yawkey estate, raising his stake to 50 percent; he would remain the Tigers' principal owner until his own death in 1935.^[2]

Yawkey left his $40 million estate to his nephew and adoptive son, Tom Yawkey,^[6] who later bought the Boston Red Sox.

A boathouse that Yawkey had constructed in 1917 in Hazelhurst, Wisconsin, was added to the National Register of Historic Places in 2009.^[7]

A cousin, Cyrus C. Yawkey, owned a lumber business and was a politician in Wisconsin.^[8]