| Lance Cpl. Patrick T. O'Day Santa Rosa, CA | |
| Sgt. Maj. Robert D. O'Dell Manassas, VA | |
| Lance Cpl. Shane K. O'Donnell DeForest, WI | |
| Spc. Justin L. O'Donohoe San Diego, CA | |
| Lance Cpl. Walter K. O'Haire Lynn, MA | |
| Pfc. Evan W. O'Neill Haverhill, MA | |
| Sgt. Michael C. O'Neill Mansfield, OH | |
| Chf. Warrant Officer Mark S. O'Steen , AL | |
| Spc. Donald Samuel Oaks Jr. Erie, PA | |
| Pfc. Francis C. Obaji Queens Village, NY | |
| Pfc. Branden F. Oberleitner Worthington, OH | |
| Spc. George R. Obourn, Jr. Creve Coeur, IL | |
| Pfc. Alex Oceguera San Bernardino, CA | |
| Sgt. 1st Class James S. Ochsner Waukegan, IL | |
| Spc. Charles E. Odums II Sandusky, OH | |
| Maj. Henry S. Ofeciar Agana, GU | |
| Sgt. John B. Ogburn, III Fruitland, OR | |
| Cpl. Wade J. Oglesby Grand Junction, CO | |
| Spc. Ramon C. Ojeda Ramona, CA | |
| Staff Sgt. Tony B. Olaes Walhalla, NC | |
| Sgt. Randell Olguin Ralls, TX | |
| Cpl. Brian Oliveira Raynham, MA | |
| Sgt. Nicholas J. Olivier Ruston, LA | |
| Spc. Toby R. Olsen Manchester, NH | |
| Lance Cpl. Daniel R. Olsen Eagan, MN | |
| Staff Sgt. Todd D. Olson Loyal, WI | |
| Cpl. John T. Olson Elk Grove Village, IL | |
| Spc. Nicholas P. Olson Novato, CA | |
| 1st Lt. Robert C. Oneto-Sikorski Bay St. Louis, MS | |
| Spc. Justin B. Onwordi Chandler, AZ | |
| Sgt. Bryan J. Opskar Princeton, MN | |
| Pfc. Michael K. Oremus Highland, NY | |
| Spc. Richard P. Orengo Toa Alta, PR | |
| Lt. Colonel Kim S. Orlando Unknown, TN | |
| Lance Cpl. Eric James Orlowski Buffalo, NY | |
| Pfc. Jay-D H. Ornsby-Adkins Ione, CA | |
| Sgt. Adrian N. Orosco Corcoran, CA | |
| 1st. Lt. Osbaldo Orozco Delano, CA | |
| Pfc. Cody J. Orr Ruskin, FL | |
| Pvt. Elijah M. Ortega Oxnard, CA | |
| Capt. Maria I. Ortiz Bayamon, PR | |
| Staff Sgt. Billy J. Orton Humnoke, AR | |
| Sgt. Timothy R. Osbey Magnolia, MS | |
| Sgt. Pamela G. Osbourne Hollywood, FL | |
| Staff Sgt. Ryan S. Ostrom Liberty, PA | |
| Chief Warrant Off. Scott A.M. Oswell , WA | |
| Lance Cpl. Deshon E. Otey Hardin, KY | |
| Pfc. Kevin C. Ott Columbus, OH | |
| Staff Sgt. Micahel C. Ottolini Sebastopol, CA | |
| Petty Officer 1st Cl Brian J. Ouellette Needham, MA | |
| Lance Cpl. Tyler R. Overstreet Gallatin, TN | |
| Sgt. Michael G. Owen Phoenix, AZ | |
| Capt. Bartt D. Owens Middletown, OH | |
| Spc. Anthony C. Owens Conway, SC | |
| Lance Cpl David Edward Owens Jr. Winchester, VA | |