The International Scientific Committee (ISC) was established at the GA Meeting on October 14, 1999, at IOI'99 in Antalya-Belek, Türkiye. For that purpose, the IOI Regulations were amended.

Former members of the ISC include:

• Isto Aho, Finland (2000 - 2001, IOI'01 HSC)
• Bojan Antolović, Croatia (2006 - 2007, Chair IOI'07 HSC)
• Zvonimir Bujanović, Croatia (2007 - 2007, Vice Chair IOI'07 HSC, ISC member)
• Hal Burch, United States of America (2002 - 2003, IOI'03 HSC)
• Benjamin Burton, Australia, (2008 - 2014, elected, host IOI'13)
• Cesar Cepeda, Mexico (2004 - 2008, elected Chair IOI'06 HSC, ISC Chair March 2007-?)
• Kyung-Yong Chwa, Korea (2000 - 2003, Chair IOI'02 HSC)
• Krzysztof Ciebiera, Poland (2004 - 2005, IOI'05 HSC)
• Gordon Cormack, Canada (2004 - 2011, Chair, IOI'2010 HSC)
• Jittat Fakcharoenphol, Thailand (2009 - 2012, Chair, IOI 2011 HSC)
• Iphigenia Founta, Greece (2002 - 2003, IOI'04 HSC)
• Greg Galperin, United States of America (2001 - 2004, Chair IOI'03 HSC)
• Mohammad Ghodsi, Iran (1999 - 2000, GA-elected)
• Roberto Grossi, Italy (2009 - 2013, host IOI'12)
• Michalis Hatzopoulos, Greece (2002 - 2005, Chair IOI'04 HSC)
• Gyula Horváth, Hungary (1999 - 2001, GA-elected, Chair IOI'96 HSC)
• Artem Iglikov, Kazakhstan (2012 - 2016, host IOI'15)
• Ossama Ismail, Egypt (2006 - 2009, Chair IOI'08 HSC)
• Marcin Kubica, Poland (2003 - 2010, elected, Chair IOI'05 HSC)
• Mansur Kutybaev, Kazakhstan (2012 - 2016, host IOI'15)
• Pangfeng Liu, Taiwan (2011 - 2015, host IOI'14)
• Mohhammad Mahdian, Iran (2015 - 2016, host IOI'17)
• Martin Mareš, Czech Republic (2006 - 2015, ITWG chair, elected, reelected 2009 and 2012)
• Pavel Mavrin, Russian Federation (2013 - 2017, host IOI'16)
• Ian Munro, Canada (2000 - 2003, elected)
• Fredrik Niemelä, Sweden (2011 - 2014, elected)
• Jyrki Nummenmaa, Finland (1999 - 2002, 2003 - 2006, Chair ITWG; Chair IOI'01 HSC)
• Xenofon Papadopoulos, Greece (2002 - 2003, IOI'04 HSC)
• Kunsoo Park, Korea (2001 - 2002, IOI'02 HSC)
• Mihai Pătraşcu, Romania (2010 - 2012, elected)
• Djura Paunic, Yugoslavia (2001 - 2004, elected)
• Lovro Pužar, Croatia (2006 - 2008, IOI'07 HSC)
• Luis Cruz Romo, Mexico (2005 - 2006, IOI'06 HSC)
• Alen Spiegl, Croatia (2006 - 2006, Temporary Chair IOI'07 HSC)
• Krzysztof Stencel, Poland (2004 - 2005, IOI'05 HSC)
• Ismail Hakki Toroslu, Türkiye (2003 - 2006, elected, Chair IOI'99 HSC, (ISC member 1999-2000, re-elected 2003)
• Velin Tzanov, Bulgaria (2007 - 2010, Chair IOI'09 HSC)
• Tom Verhoeff, Netherlands (2005 - 2007, elected, Chair IOI'95 HSC, ISC member 1999-2005, re-elected 2005, ISC Chair 1999-March 2007)
• Wenhu Wu, China (1999 - 2000, Chair IOI 2000 HSC)
• Baolin Yin, China (1999 - 2001, Vice-Chair IOI 2000 HSC)
• Francisco Zaragoza Martínez, Mexico (2005 - 2006, IOI'06 HSC)
• Hamid Zarrabi-Zadeh, Iran (2014 - 2015, host'17)
• Richard Peng, USA (2014 - 2018, elected at IOI'14, re-elected at IOI'15)
• Tetsushi Ito, Japan (2015-2019, host IOI'18)
• Farid Ahmadov, Azerbaijan (2016 - 2020, host IOI'19)
• Mohamed AbdElWahab, Egypt (2018 - 2020, host of postponed IOI'21)
• Gan Wei Liang, Singapore (2017 - 2022, host IOI'20 and IOI'21)
• Jakub Łącki, Poland (2013 - 2022: elected at IOI'13, re-elected at IOI'16, re-elected at IOI'19, re-elected at IOI'21)
• Mikhail Tikhomirov (2019 - 2023, elected at IOI'19)
• Jonathan Irvin Gunawan, Indonesia (2017 - 2019, 2019 - 2023, elected at IOI'17, host IOI'22)
• Zsolt Németh, Hungary (2020 - 2024, host IOI'23)
• Michal Forišek, Slovakia (2021 - 2024, elected at IOI'21; 2006 - 2013: elected at IOI'06, re-elected at IOI'09, re-elected at IOI'12; 2014 - 2017: elected at IOI'14)