Members A-Z since 1949

Mr Fergus O'BRIEN Ireland Joined in 1991, left in 1993

Mr Nikola OBULJEN Croatia Joined in 1997, left in 2000

Mr Muammer OBUZ Türkiye Joined in 1963, left in 1965

Baroness Detta O'CATHAIN United Kingdom Joined in 2009, left in 2009

Mr Achille OCCHETTO Italy Joined in 2001, left in 2006

Mr Cuauhtémoc OCHOA FERNÁNDEZ Mexico Joined in 2025

Ms Jennifer O'CONNELL Canada Joined in 2016, left in 2025

Mr Timothy O'CONNOR Ireland Joined in 1968, left in 1970

Mr Beka ODISHARIA Georgia SOC Joined in 2020, left in 2021

Mr Saïd ODYAK Türkiye Joined in 1949, left in 1950

Mr Cevad ODYAKMAZ Türkiye Joined in 1956, left in 1966

Mr Jean OEHLER France Joined in 1981, left in 1993

Mr Ulrich OEHME Germany EC/DA Joined in 2018, left in 2022

Mr Franz OEHRI Liechtenstein Joined in 1981, left in 1986

Ms Judith OEHRI Liechtenstein ALDE Joined in 2013, left in 2017

Mr Walter OEHRY Liechtenstein Joined in 1989, left in 1994

Ms Kristen OESTERGAARD Denmark Joined in 1964, left in 1973

Mr Josef OESTERLE Germany Joined in 1954, left in 1957

Ms Jolanda OFFENBECK Austria Joined in 1979, left in 1991

Mr Rainer OFFERGELD Germany Joined in 1974, left in 1975

Mr Kristian OFTEDAL Norway Joined in 1949, left in 1949

Mr Tor OFTEDAL Norway Joined in 1974, left in 1975

Ms Gudrún ÖGMUNDSDÓTTIR Iceland Joined in 2005, left in 2007

Mr Yalçin ÖĞÜTCAN Türkiye Joined in 1995, left in 1996

Mr Orhan OĞUZ Türkiye Joined in 1972, left in 1975

Mr Edward O'HARA United Kingdom Joined in 1997, left in 2010

Mr Shimon OHAYON Israel Joined in 2014, left in 2015

Mr Thomas F. O'HIGGINS Ireland Joined in 1950, left in 1973

Mr Bertil G. OHLIN Sweden Joined in 1949, left in 1971

Ms Carina OHLSSON Sweden SOC Joined in 2003, left in 2022

Mr Conny ÖHMAN Sweden Joined in 2003, left in 2007

Mr Ioannis OIKONOMOU Greece EPP/CD Joined in 2024

Ms Kristiina OJULAND Estonia Joined in 1995, left in 2009

Ms Nilgün ÖK Türkiye NR Joined in 2023, left in 2023

Mr Jim O'KEEFFE Ireland EPP/CD Joined in 1991, left in 2011

Mr Batt O'KEEFFE Ireland Joined in 1993, left in 1993

Mr İbrahim ÖKTEM Türkiye Joined in 1962, left in 1974

Mr Zeki OKUR Türkiye Joined in 1975, left in 1980

Mr Kjartan ÓLAFSSON Iceland Joined in 2002, left in 2003

Mr Franz OLAH Austria Joined in 1959, left in 1962

Mr Lajos OLÁH Hungary NR Joined in 2018, left in 2021

Mr Lorenzo OLARTE Spain Joined in 1993, left in 1995

Mr Bergþór ÓLASON Iceland ECPA Joined in 2018

Mr John O'LEARY Ireland Joined in 1973, left in 1975

Mr Liubov OLEINIK Russian Federation* Joined in 1996, left in 2000

Mr Yury OLEINIKOV Russian Federation* NR Joined in 2019, left in 2022

Mr Juozas OLEKAS Lithuania Joined in 2000, left in 2003

Mr Józef OLEKSY Poland Joined in 1997, left in 1998

Mr Boris OLIJNIK Ukraine Joined in 1994, left in 2006

Mr Kalevi OLIN Finland Joined in 2003, left in 2007

Mr Francisco OLIVEIRA DIAS Portugal Joined in 1977, left in 1977

Mr Guilherme d' OLIVEIRA MARTINS Portugal Joined in 2005, left in 2006

Mr John OLIVER Canada Joined in 2016, left in 2019

Mr Gerardo OLIVERIO Italy Joined in 2001, left in 2005

Mr Rosario OLIVO Italy Joined in 1996, left in 2001

Ms Barbara OLIWIECKA Poland ALDE Joined in 2024, left in 2025

Ms Kathrine OLLDAG Denmark ALDE Joined in 2019, left in 2022

Mr Erich OLLENHAUER Germany Joined in 1950, left in 1953

Baroness Nuala O'LOAN United Kingdom NR Joined in 2015, left in 2016

Ms Fiona O'LOUGHLIN Ireland ALDE Joined in 2020, left in 2025

Mr Tomas Ingi OLRICH Iceland Joined in 1995, left in 2002

Mr Erling OLSEN Denmark Joined in 1964, left in 1966

Mr Gunnel OLSSON Sweden Joined in 1953, left in 1959

Mr Kent OLSSON Sweden Joined in 2007, left in 2010

Mr Paweł OLSZEWSKI Poland EPP/CD Joined in 2012, left in 2014

Mr Ionel OLTEANU Romania Joined in 2001, left in 2005

Mr Hryhoriy OMELCHENKO Ukraine Joined in 2006, left in 2010

Mr Odd OMLAND Norway SOC Joined in 2013, left in 2014

Mr Pieter OMTZIGT Netherlands EPP/CD Joined in 2004, left in 2025

Ms Altynai OMURBEKOVA Kyrgyzstan Joined in 2016, left in 2019

Mr Mario ONAINDIA Spain Joined in 1996, left in 2000

Mr Ihsan ONAL Türkiye Joined in 1962, left in 1963

Mr Suat ÖNAL Türkiye EC Joined in 2014, left in 2018

Ms Fatma ÖNCÜ Türkiye NR Joined in 2023

Mr Abdülkadir Emin ÖNEN Türkiye EC Joined in 2011, left in 2015

Ms Tülay ÖNEY Türkiye Joined in 1985, left in 1988

Mr Vedat ÖNSAL Türkiye Joined in 1975, left in 1976

Mr Cranley ONSLOW United Kingdom Joined in 1977, left in 1981

Ms Leyla ONUR Germany Joined in 2001, left in 2003

Mr Oleksandr ONYSCHENKO Ukraine EC Joined in 2013, left in 2015

Mr D.A. Th. van OOIJEN Netherlands Joined in 1973, left in 1977

Ms Ria OOMEN-RUIJTEN Netherlands EPP/CD Joined in 2015, left in 2023

Mr Sherig-ool OORZHAK Russian Federation* Joined in 1996, left in 2002

Mr Rudolf OPITZ Germany Joined in 1975, left in 1977

Mr Gerrit-Jan OPLAAT Netherlands NR Joined in 2023, left in 2024

Mr Mart OPMANN Estonia Joined in 2003, left in 2005

Mr Mario-Ovidiu OPREA Romania Joined in 2007, left in 2009

Mr Hans OPRECHT Switzerland Joined in 1963, left in 1964

Mr Oguz ORAN Türkiye Joined in 1962, left in 1966

Mr Joseph O'REILLY Ireland EPP/CD Joined in 2008

Mr Patrick O'REILLY Ireland Joined in 1962, left in 1965

Mr Marcelino OREJA Spain Joined in 1983, left in 1984

Mr Luis Alberto ORELLANA Italy SOC Joined in 2013, left in 2018

Mr Michael OREN Israel Joined in 2015, left in 2016

Mr Apostolos ORFANIDIS Greece Joined in 1949, left in 1949

Mr Franco Luigi ORIONE Italy Joined in 1980, left in 1984

Mr Andrea ORLANDO Italy SOC Joined in 2018, left in 2025

Mr Mirosław Adam ORLIŃSKI Poland EPP/CD Joined in 2024

Ms Ann ORMONDE Ireland Joined in 2004, left in 2007

Mr Paul d' ORNANO France Joined in 1992, left in 1993

Ms Lesia OROBETS Ukraine EPP/CD Joined in 2013, left in 2015

Mr Hüseyin ÖRS Türkiye NR Joined in 2020, left in 2023