Appleton is a city in the U.S. state of Wisconsin, on the Fox River, 100 miles (161 km) northwest of Milwaukee. As of the 2000 census, the city had a total population of 70,087. It is the county seat of Outagamie County^GR6, but extends into both Calumet County and Winnebago County.

Appleton was the childhood home (but not the birthplace as he sometimes claimed) of magician Harry Houdini, author Edna Ferber and Iwo Jima flag-raiser John Bradley, and is the birthplace of actor Willem Dafoe, and football player Rocky Bleier. Sen. Joseph McCarthy, who was born nearby in Grand Chute, Wisconsin, is buried in Appleton, in St. Mary's Parish Cemetery. Appleton also had the first telephone in all Wisconsin, the first Chinese restaurant in Outagamie County, and the first incandescent light in any city beyond the East Coast.

The first hydroelectric power was generated in Appleton, on the Fox River.

The city has commercial air service provided at Outagamie County Regional Airport.

The Valley Fair Mall, recognized as the first enclosed shopping mall in the United States, was built in Appleton in 1954, and will be mostly destroyed in 2006, pending the sale from the previous (now bankrupt) mall owners, Youthfutures INC.