- O'Callaghan, Paul
- O'Connor, Emma
- O'Connor, H. E.
- O'Connor, T. P.
- O'Donnell, Lisa
- O'Donovan, Miss M. A.
- O'Driscoll, Captain P. D.
- O'Gorman, Edmund
- O'Leary, Michael
- O'Loughlin, Rev. Gordon
- O'Mahony, B. M. E.
- O'Neill, Carol
- O'Neill, Martin
- O'Neill, Michael
- O'Neill, Peter
- O'Shea, E. W.
- Oakensen, Derek John
- Oakes, Fergus
- Oakes, Peter
- Oakland, Michael
- Oakley, Kenneth Page
- Oaksden, Dr. Derek John
- Oates, Jonathan
- Ockenden, Michael
- Odell, Julia A.
- Odell, Mary Theresa
- Offen, Edwin R.
- Offer, Mrs. Elizabeth Mary
- Offord, Mary
- Ogburn, Frederick John
- Ogden, Muriel
- Ogden, Peter
- Ogilvie, Marilyn Bailey
- Ogley, Bob
- Okasha, Elisabeth
- Olaves, Meriel St
- Oldfield, Tony
- Oldmeadow, Ernest
- Olive, Martin F.
- Oliveira, da Luz
- Oliver, L. K.
- Oliver, Vere F. M.
- Oliver, W.
- Ollard, Richard Lawrence
- Ollerenshaw, Neville
- Olliver, Sylvia
- Olson, Dr. Alison
- Oppitz, Leslie
- Oram, Richard
- Orchard, Stephen C.
- Orchard-Webb, Dr. Johanne Marie
- Orger, E. R.
- Oriel, S. A.
- Ormiston, Eunice N.
- Orna-Ornstein, John
- Orr, Rose
- Orr, Valerie
- Orr, Rev. Edward Percival
- Orrell, J.
- Orton, Clive
- Osborn, J.
- Osborn, J. Lee
- Osborne, Julian
- Osborne, Noel Howard
- Osborne, Ray
- Osborne, Dr. Bruce E.
- Osbourne, Barbara
- Osmond, Nick
- Osowiecki, Dr. Maria
- Ostoja-Zagorski, J.
- Oswald, Arthur
- Oswald, Neville
- Ottaway, Patrick
- Otter, Rev. W. Bruere
- Otter, Sir John
- Ouden, Alex den
- Ould, Herman
- Outen, A. F.
- Ouvry, Frederic
- Ovenden, Dennis C.
- Ovenden, Richard
- Ovenden, Dr. Peter J.
- Overbey, Kathleen Eileen
- Owen, Diana
- Owen, H. G.
- Owen, James
- Owen, June
- Owen, Nicholas
- Owen, Patricia
- Owen, Rupert K. W.
- Owen, Dr. J. B.
- Owen-Crocker, Prof. Gale R.
- Owens, J. S.
- Owens, Norah
