NBACharles Oakley 1985-86 to 2003-04
NBACharles O'Bannon 1997-98 to 1998-99
NBAEd O'Bannon 1995-96 to 1996-97
NBAFabricio Oberto 2005-06 to 2010-11
WNBATeja Oblak 2026
ABAJimmy O'Brien 1973-74 to 1974-75
ABAJim O'Brien 1973-74 to 1974-75
NBAJ.J. O'Brien 2015-16
NBAJohnny O'Bryant 2014-15 to 2017-18
NBAPatrick O'Bryant 2006-07 to 2009-10
NBADaniel Ochefu 2016-17
NBAGreg Oden 2008-09 to 2013-14
NBALamar Odom 1999-00 to 2012-13
WNBALeaonna Odom 2020 to 2021
NBAJosh Oduro 2025-26
WNBAYuko Oga 2008
NBAAlan Ogg 1990-91 to 1992-93
WNBAArike Ogunbowale 2019 to 2026
WNBAChiney Ogwumike 2014 to 2023
WNBANneka Ogwumike 2012 to 2026
WNBAJenna O'Hea 2011 to 2016
NBATim Ohlbrecht 2012-13
WNBANicole Ohlde 2004 to 2010
NBASemi Ojeleye 2017-18 to 2021-22
NBAEmeka Okafor 2004-05 to 2017-18
NBAJahlil Okafor 2015-16 to 2024-25
NBAToby Okani 2025-26
NBAChuma Okeke 2020-21 to 2024-25
NBAElie Okobo 2018-19 to 2019-20
NBAJosh Okogie 2018-19 to 2025-26
NBAOnyeka Okongwu 2020-21 to 2025-26
WNBAAmy Okonkwo 2025 to 2026
NBAMike O'Koren 1980-81 to 1987-88
NBAIsaac Okoro 2020-21 to 2025-26
WNBAMadina Okot 2026
NBAKZ Okpala 2019-20 to 2022-23
NBAMehmet Okur 2002-03 to 2011-12
NBAVictor Oladipo 2013-14 to 2022-23
WNBAAbi Olajuwon 2010 to 2011
NBAHakeem Olajuwon 1984-85 to 2001-02
ABAMark Olberding 1975-76
NBAMark Olberding 1976-77 to 1986-87
NBALachlan Olbrich 2025-26
NBAJawann Oldham 1980-81 to 1990-91
NBAFrank Oleynick 1975-76 to 1976-77
NBAQuincy Olivari 2024-25
NBABrian Oliver 1990-91 to 1997-98
NBACameron Oliver 2020-21 to 2021-22
NBADean Oliver 2001-02 to 2002-03
NBAJimmy Oliver 1991-92 to 1998-99
NBAJohn Olive 1978-79 to 1979-80
NBAKevin Ollie 1997-98 to 2009-10
NBAMichael Olowokandi 1998-99 to 2006-07
WNBALucy Olsen 2025 to 2026
NBAKelly Olynyk 2013-14 to 2025-26
NBANorchad Omier 2025-26
NBAEugene Omoruyi 2021-22 to 2023-24
NBAJermaine O'Neal 1996-97 to 2013-14
NBARoyce O'Neale 2017-18 to 2025-26
NBAShaquille O'Neal 1992-93 to 2010-11
WNBAJennifer O'Neill 2015
WNBAKristen O'Neill 2008
NBAMiye Oni 2019-20 to 2021-22
NBAArinze Onuaku 2013-14 to 2016-17
NBAChinanu Onuaku 2016-17 to 2017-18
WNBAMichaela Onyenwere 2021 to 2026
WNBAUgonne Onyiah 2026
NBAKyle O'Quinn 2012-13 to 2019-20
WNBAInga Orekhova 2014 to 2015
NBALouis Orr 1980-81 to 1987-88
NBAJose Ortiz 1988-89 to 1989-90
NBADaniel Orton 2011-12 to 2013-14
WNBACharisma Osborne 2024 to 2026
WNBAIrina Osipova 2006
NBACedi Osman 2017-18 to 2023-24
NBAGreg Ostertag 1995-96 to 2005-06
NBADan O'Sullivan 1990-91 to 1995-96
NBAMatt Othick 1992-93
NBADaniel Oturu 2020-21 to 2021-22
NBAKelly Oubre Jr. 2015-16 to 2025-26
NBABo Outlaw 1993-94 to 2007-08
NBATravis Outlaw 2003-04 to 2013-14
NBADoug Overton 1992-93 to 2003-04
WNBAHeather Owen 1999 to 2000
NBAAndre Owens 2005-06 to 2007-08
NBABilly Owens 1991-92 to 2000-01
NBAChris Owens 2002-03
NBAEddie Owens 1977-78
NBAJim Owens 1973-74 to 1974-75
NBAKeith Owens 1991-92
NBALarry Owens 2010-11 to 2011-12
WNBAShantia Owens 2000 to 2002
NBATariq Owens 2019-20
NBATom Owens 1976-77 to 1982-83
ABATom Owens 1973-74 to 1975-76
NBARay Owes 1996-97
NBAOlumide Oyedeji 2000-01 to 2002-03