William Sykes
William or Bill Sykes may refer to:
- Bill Sykes, Member for Benalla in the Victorian Parliament
- Bill Sykes , English chaplain and author
- William Sykes , convict transported to Western Australia
- William Sykes , Anglican clergyman
- William Sykes , English manufacturer of sporting goods
- William [Henry Sykes], Indian Army officer
- William Sykes , English clergyman and cricketer
- William Robert Sykes, British engineer from London
- William Stanley Sykes, British anaesthetist and crime writer
- Charles Henry Sykes, known as Bill, American cartoonist