Abdelhamid Abaaoud (Arabic: عبد الحميد ابعود, romanized: ʿAbd al-Ḥamīd ʾAbā ʿŪd; 8 April 1987 – 18 November 2015) was a Belgian-born French Islamic terrorist who had spent time in Syria and was suspected of having organized multiple terror attacks in Belgium and France, and is known to have masterminded and participated in the November 2015 Paris attacks. Prior to the Paris attacks, there was an international arrest warrant issued for Abaaoud for his activities in recruiting individuals to Islamic terrorism in Syria.

Abaaoud was also known as Abu Omar Soussi (Arabic: أبو عمر السوسي, meaning "Abu Omar the Susian", his Moroccan family's place of origin) and as Abu Omar al-Baljīkī (Arabic: أبو عمر البلجيكي, meaning Abu Omar the Belgian), both of which were noms de guerre.

He died from wounds received during an armed raid conducted by French authorities in the suburb of Saint-Denis in north Paris.

Abdelhamid, one of six children, was born on 8 April 1987 in Anderlecht, a municipality of Brussels, Belgium. He was the son of Omar Abaaoud, who emigrated to Belgium from Morocco in 1975. Omar Abaaoud's first employment after emigration was in mining, before he was employed as a shopkeeper.

Abaaoud grew up in Molenbeek, an area in Brussels where "the radical Salafi ideology has flourished among some young Muslims." He attended the select Collège Saint-Pierre [fr] in Uccle from 1999 to 2000. An article from 2015 said childhood friends claimed Abaaoud had smoked "a lot of cannabis" during his teenage years.

Both Abaaoud and Salah Abdeslam were arrested during December 2010 for attempting to break into a parking garage, according to the lawyer representing Abaaoud. Abaaoud alone had spent time in at least three prisons, and had a number of arrests for assault, and other crimes. The nature of these latter crimes were not disclosed by his lawyer. For a time, sometime prior to 2013, Abdelhamid Abaaoud was involved in trading via employment with his father.

In 2013, he recruited his then 13-year-old brother Younes to join him in Syria. They left for Syria on 19 January 2014, for which he was convicted of abduction, having been previously convicted of robbery. On 24 January 2018 during the trial of Jawad Bendaoud, the president of the court Isabelle Prévost-Desprez announced the death of Younes in an Iraqi-Syrian zone.

Abaaoud is reported to have joined a group within ISIL known as al-Battar Katiba, (the al-Battar Battalion) during the fight against Bashar al-Assad in 2013. He returned to Belgium by the end of the same year. In 2014, independent journalists Étienne Huver and Guillaume Lhotellier visited the Syria–Turkey border, where they obtained photos and video of Abaaoud's time in Syria. One portion of this material showed Abaaoud and others loading bloody corpses into a truck and trailer before Abaaoud grinned and told the camera: "Before we towed jet skis, motorcycles, quad bikes, big trailers filled with gifts for vacation in Morocco. Now, thank God, following God's path, we're towing apostates, infidels who are fighting us." Within Syria, Abaaoud is known to have been active at Hraytan. A diary entry while there records: "Admittedly there is no joy in spilling blood, although it's nice to see, from time to time, the blood of the infidels".