 | O'Daniel, John W., Jr. | | 20-09-1944 |  |
| O'Arie, Nic | 10-07-1918 | 13-04-1945 |  |
| O'Barr, William Connie "Bill" | 29-04-1923 | 13-04-2006 |   |
| O'Brien, Frank Michael | 31-03-1875 | 00-09-1943 |  |
| O'Brien, Gordon | | 09-02-1945 | |
| O'Brien, Henry J. | | |  |
| O'Brien, J.J. | | 11-01-1944 |  |
| O'Brien, James | 18-06-1923 | 15-06-1945 | |
| O'Brien, Robert F. | | |  |
| O'Brien, Terence M. | | 03-03-1945 | |
 | O'Brien, William J. | 00-00-1899 | 07-07-1944 |  |
| O'Brien, William P. | | |  |
 | O'Bryan, Joseph R. | | | |
| O'Bryant, Virgil L. | | | |
 | O'Callahan, Joseph Timothy "Father Joe" | 14-05-1904 | 18-03-1964 |      |
| O'Connell, Gerald Moore (Jr.) | 04-04-1922 | 04-08-1944 | |
| O'Connell, Melvin Donald | 06-06-1911 | 10-12-1941 | |
 | O'Connell, Phillip B. "Phil" | | 28-10-1942 | |
| O'Connell, Robert | | | |
| O'Connell, Robert William | | |  |
| O'Conner, Gerard J. | | 04-07-2006 | |
 | O'Connor, James Joseph | 16-09-1928 | 17-03-1945 | |
| O'Connor, William Farrell | 19-10-1895 | 17-10-1918 | |
 | O'Daniel, John Wilson "Iron Mike" | 15-02-1894 | 27-03-1975 |   more |
| O'Day, George | | | |
| O'Dea, Cifford J. "John" | | 12-04-1945 | |
| O'Dell, Loren E. | | | |
| O'Donovan, John F. | | | |
| O'Farrell, Hugh R. | 11-05-1914 | |  |
| O'Farrell, Rufus E. | 24-07-1917 | 10-04-1943 | |
| O'Flaherty, William J. | | | |
| O'Grady, David Thomas | 25-03-1924 | 17-12-1944 | |
| O'Grady, Martin J. | | 30-04-1945 | |
| O'Hara, Leonard William | | 16-06-1942 | |
 | O'Hare, Edward Henry "Butch" | 13-03-1914 | 26-11-1943 |  more |
 | O'Kane, Richard Hetherington "Dick" | 02-02-1911 | 16-02-1994 | more |
| O'Keefe, Arthur J. | | | |
| O'Keefe, Patrick S. "Patty" | 03-04-1926 | 08-02-2003 |    |
| O'Leary, Donoval L. | | | |
| O'Leary, Frank | | 23-11-1944 | |
| O'Meara, Joseph D. | | 31-01-1944 | |
| O'Meara, Thomas F. | | 12-01-1945 | |
| O'Meara, William A. | | 02-01-1945 | |
| O'Neal, Levi | | | |
| O'neill, Clarence | | | more |
| O'Neill, James Joseph | 16-07-1925 | 20-08-1944 | |
| O'Neill, John J. | | | |
| O'Neill, William J. | | | |
| O'Scoggin, Eulus (Jr.) | 10-10-1920 | 06-07-1944 | |
| O'Toole, Alphonsus Lawrence | | | |
| Oakley, Benjamin T. | | | |
 | Oakley, Thomas Benjamin Jr. | 27-02-1912 | 08-11-1944 | |
| Oakman, George P. | | | |
| Oaks, Orville | | | |
| Oates, Charles R. | | | |
| Oba, Snichi | 27-02-1922 | 21-08-1944 | |
| Oberg, Oliver E. | | | |
| Obernolte, Clyde H. | | |  |
| OBerry, Louie, A. | | | |
 | Obourn, Robert Lyle | 20-01-1919 | 27-03-1992 |  |
| Obregon, Eugene Arnold | 12-09-1930 | 26-09-1950 |    |
| Ochacher, Hyman | | | |
| OConnor, Thomas, F. | | | |
| Odegard, Henry O. | | | |
| Oden, Delk McCorkle | 13-07-1911 | 13-06-1997 | |
| Odenbrett, Harvey G. | | | |
| Odom, Hubert | | | |
| Odom, Millard | | 20-11-1943 | |
| Odum, Jerry L. | | 25-02-1945 | |
| Oehlert, Herschel Allen, Jr. | | | |
| Ofchinick, Richard P. | | 18-09-1944 | |
 | Ofstie, Ralph Andrew | 16-11-1897 | 19-11-1956 | more |
| Oftedahl, Lawrence D. | | | |
| Ogburn, William R. | 04-07-1920 | | |
 | Ogden, Carlos Carnes | 09-05-1917 | 02-04-2001 | more |
 | Ogden, David Ayres Depue | 16-10-1897 | 26-11-1969 | |
| Ogden, Edward L. | | 13-04-1945 | |
| Ogden, Hayes Chick | 00-00-1918 | 12-08-1944 | |
| Ogden, Raymond | | | |
| Ogden, William Stephen | | | |
| Oglensky, David | | 25-02-1945 | |
| Ohama, Abraham G. "Abe" | | 20-10-1944 | |
 | Ohata, Allan M. | 13-09-1918 | 17-10-1977 | |
 | Ohman, Daniel Victor | 04-03-1918 | 30-07-1943 | |
| Oiye, George "Whitey" | 19-02-1922 | |  |
| Okamoto, Tomiso | 18-02-1924 | 06-07-1944 | |
| Okubo, James K. | 30-05-1920 | 29-01-1967 |  |
 | Okutsu, Yukio | 03-11-1921 | 24-08-2003 | |
| Oland, Carl Warner | 00-00-1922 | 13-09-1943 | |
| Olbert, Richard N. | | | |
| Old, Abner Hansell | 26-04-1886 | 22-02-1920 | |
| Olden, Fred A., Jr. | | | |
 | Oldendorf, Jesse Barett | 16-02-1887 | 27-04-1974 |  more |
| Older, Harold K. | | | |
| Oldfield, Leonard G. | | | |
| Olds, Robin | 01-07-1922 | 14-06-2007 |   more |
| Oleson, Harold R. A. | | | |
| Oleson, John E. | | | |
| Oliva, G. | | | |
| Oliver, Bernard J. | | 25-02-1945 | |
| Oliver, Raymond L. | | | |
 | Oliver, Thomas W. | 17-03-1923 | 17-12-1944 | |
| Oliver, William B. | | | |
| Olivier, Leonce | | | |
| Olmstead, Earl, G. | | | |
| Olmstead, John M. | | | |
| Olney, Sheldon | | | |
| Olsen, Barney | | 10-02-1945 | |
| Olsen, Earl K. | | | |
| Olsen, Eugene R. | | | |
| Olsen, Fred J. | | | |
| Olsen, John | | | |
| Olsen, William B. | | | |
| Olson, Albert N. | | | |
 | Olson, Arlo L. | 20-04-1918 | 27-10-1943 | |
| Olson, George O. | 00-00-1911 | 18-07-1943 |  |
| Olson, Halbert E. | | | |
| Olson, Hardin L. | | | |
| Olson, John E., Jr. | | 22-12-1943 | |
| Olson, John Walter | 24-12-1915 | 09-10-1942 | |
| Olson, Richard J. | | | |
| Olson, Robert Dale | | | |
| Olson, Robert Evans | | | |
| Olson, Robert O. | | | |
 | Olson, Truman O. | 13-10-1917 | 30-01-1944 | |
| Olson, Virgil Willis | 06-10-1912 | 19-08-1941 | |
| Omark, Warren Roderick | | | |
 | Onana, Ralph Wheeler (O'Nan) | 06-10-1935 | 01-11-1965 |    more |
| ONeill, Rich, J. | | | |
| Ono, Frank H. | 05-06-1923 | 06-05-1980 | |
| Onoff, John Philip | 04-05-1920 | 02-12-2018 | |
| Onorato, Jordan Paul | | | |
| Onouye, Hiroji | 01-03-1890 | 30-04-1944 | |
| Oot, Earl L. | | | |
| Opalenik, Steven Henry | 11-08-1916 | 22-02-1945 | |
| Opdyke, Chester P., Jr. | | | |
| Oppenheimer, Julius Robert | 22-04-1904 | 18-02-1967 |    |
| Oquendo, William Caesar | | 20-06-1942 | |
 | Oresko, Nicholas | 18-01-1917 | 04-10-2013 | more |
| Organski, Zorack | | | |
| Oribiletti, Bruno | | | |
 | Orleck, Joseph | 22-06-1906 | 09-09-1943 | |
| Orme, George E. | | | |
| Orndorff, Douglas | | | |
| Orr, Albert I. | | | |
| Orr, Ray F. | | | |
| Orr, Willard F. | | | |
| Orsini, Joseph J. | 22-10-1925 | 12-04-1945 | |
| Ortego, Ralph | | | |
| Orth, John | | | |
| Ortiz, Ernesto S. | | | |
 | Ortiz, Louis | 00-00-1925 | | |
 | Ortiz, Pierre (Peter) Julien | 05-08-1913 | 16-05-1988 |    more |
| Ortiz, Robert Manuel | | | |
| Ortiz, Robert, I. | | | |
| Orvin, Louis Ernest, Jr. "Lukie" | 20-03-1922 | 04-12-2008 | |
| Osberg, Carl August | 13-04-1920 | 04-06-1942 | |
| Osborn, Stanley E. | | | |
| Osborne, John Donald | 07-10-1917 | 17-12-1944 | |
 | Osborne, Walter H. Jr. | 02-06-1923 | 20-08-1945 | |
| Oshiro, Sam Y. | 16-02-1921 | 01-11-1944 | |
| Oshlo, Richard C. "Dick" | 26-02-1921 | 30-05-1975 |   |
| Osiek, Leonard F. | | 31-07-1944 | |
| Oskamp, Clifford G. | 00-00-1920 | 17-08-1943 |  |
| Oskins, Robert D. | | | |
 | Osmus, Wesley Frank | 02-09-1918 | 04-06-1942 | |
| Ostberg, Edwin J. | | | |
| Ostendorf, Herman J. | | | |
| Ostenrude, Ervin | | | |
| Oster, Frank J. | | | |
| Oster, James Charles | | | |
| Osterberg, Norman A. | | | |
| Ostrander, Dean, L. | | | |
| Ostrom, Charles E. | | 20-09-1944 | |
 | Ostrowski, Wallace William "Wally" | 10-12-1921 | 15-12-2004 | more |
| Ostrum, Melvin J. | | | |
| Oswald, Elmer W. | | | |
| Oswald, Robert J., Jr. | | | |
| Otani, Douglas K. | 13-10-1916 | 02-06-1944 | |
 | Otani, Kazuo | 02-06-1918 | 15-07-1944 | |
| Otsuka, Jiro | 06-04-1923 | 03-06-1944 | |
| Ott, Edward V. | 16-02-1915 | 19-02-1999 | |
| Ott, Elsie S. | | | |
| Ott, Lambert B. | | | |
 | Otter, Bethel Veech | 12-09-1914 | 06-05-1942 | |
| Ottinger, George Malone | | 24-03-1945 | more |
 | Otton, Robert Aubrey | 05-03-1926 | 19-02-1945 | |
 | Ouellette, Raymond L. | 21-03-1921 | 20-05-1943 | |
| Oughton, Walter C. | 03-07-1923 | 27-03-1943 | |
| Outerbridge, William W. | | | |
| Outerson, William | 29-12-1909 | |  |
 | Outlaw, Edward Cobb | 29-09-1914 | 05-03-1996 | |
| Overall, Sidney R. | | | |
| Overman, Ellis | | | |
| Overmyer, Eugene E. | | | |
| Overton, Edward White, Jr. | | | |
| Owen, Fred St. Clair | 19-08-1878 | 13-10-1918 | |
| Owen, Thomas Marvin | | | |
 | Owens, Claude Calvin | 23-12-1920 | 30-11-1944 | |
| Owens, Frank H. | | | |
| Owens, Gordon N. | | | |
| Owens, James Charles, Jr. | | | |
| Owens, James J., | | | |
| Owens, Ralph | | | |
 | Owens, Robert Allen | 13-09-1920 | 01-11-1943 | |
 | Owens, Robert Gordon, Jr. | 13-02-1917 | 31-10-2007 | more |
| Owens, Robert, V. | | | |
| Owens, Seymour Dunlop (USN) | | | |
| Owens, Virgil R. | | | |
| Ownby, Bryan | | | |
| Owned, Bryan | | | |
| Ownes, Estile, I. | | | |
| Oyabu, Harumatsu | | 21-04-1945 | |
 | Ozbourn, Joseph William | 24-10-1919 | 30-07-1944 |   more |
| O’Bannon, Wilcie A. | 18-05-1922 | | |
| O’Beirne, Emmet | | | |
| O’Brien, Martin J. | | | |
 | O’Brien, William H. "O’Be" | | 12-05-1944 | |
| O’Dowd, Jerome J. | | | |
| O’Flaherty, Frank Woodrow | | | |
| O’Hearn, Mathew Charles, Jr. | | | |
| O’Keefe, Jeremiah Joseph | | | |
| O’Neil, Guy Edward, Jr. | | | |
| O’Reagan, William V. | | | |
 | O’Reilly, Martin G. | | 04-07-1945 | |
 | O’Rourke, Vincent Patrick | 19-05-1922 | 14-07-2011 | more |
| O’Toole, John A. | | | |
| O’Toole, Joseph P. | | | |
