William Neilson
William Neilson may refer to:
- William Neilson (Lord Provost), Lord Provost of Edinburgh 1717 to 1719
- William Neilson (businessman), Canadian businessman
- William Neilson (Manitoba politician), physician and politician in Manitoba, Canada
- Willie Neilson, Scottish rugby player
- William Allan Neilson, Scottish-American educator
- William Neilson (cricketer), English-born New Zealand cricketer
- William George Neilson, Canadian politician in the Legislative Assembly of British Columbia
- Bill Neilson, Premier of Tasmania