William Harper
William, Will, Willie, Bill, or Billy Harper may refer to:
Arts and entertainment
- William A. Harper, Canadian-born artist
- Billy Harper, American jazz saxophonist
- William Claude Harper, American jewelry artist
- William Harper (composer), American composer and photographer
- William Jackson Harper, American actor
Law and politics
- William Harper (South Carolina politician), US Senator from South Carolina
- William Harper (Louisiana politician), American politician in Louisiana
- William Harper (Rhodesian politician), Royal Air Force pilot and Rhodesian politician
Sports
Association football (soccer)
- Billy Harper (footballer, born 1877), English footballer
- Bill Harper (footballer, born 1897), Scottish football goalkeeper
- Billy Harper (footballer, born 1897), English footballer
- Bill Harper (footballer, born 1900), Scottish football goalkeeper
Other sports
- Bill Harper (baseball), American baseball pitcher
- Bill Harper (soccer), Canadian soccer player
- Willie Harper, American football linebacker
Others
- William Rainey Harper, American academic, first president of the University of Chicago
- William Edmund Harper, Canadian astronomer
- William Harper Jr., American pioneer aviator with the Wright brothers