O
- Nicholas A. O'Donoughue
- Claire E. O'Hanlon
- Kelsey O'Hollaren
- Angela O'Mahony
- Oscar O'Mara
- Theodora Ogden
- Miyeon Oh
- Chad J. R. Ohlandt
- Sarah Ohls
- Brittney Ojewumi
- Edward N. Okeke
- Ian Olfarnes
- Stephen W. Oliver, Jr.
- Stuart S. Olmsted
- Fifi Olumogba
- Isaac M. Opper
- Scott Orr
- Bruce R. Orvis
- Jan Osburg
- Umut Ozek