Kennelly is a surname and may refer to:
- Ardyth Kennelly, American novelist
- Arthur Edwin Kennelly, American engineer
- Barbara B. Kennelly, Connecticut Representative
- Brendan Kennelly, Irish poet and novelist
- Keala Kennelly, American surfer
- Martin H. Kennelly, mayor of Chicago
- Matthew F. Kennelly, Federal District Court Judge in Illinois
- Pat Kennelly, Australian politician
- Ryan Kennelly, American powerlifter
- Sheila Kennelly, Australian actress
- Tadhg Kennelly, Irish Gaelic football player
- Tim Kennelly, Irish Gaelic football player
Kennelly may also refer to:
- Kennelly–Heaviside layer, a layer of the Earth's ionosphere