Omar Bakri Muhammad (Arabic: عمر بکری محمد; born Omar Bakri Fostock; 1958) is a Syrian Islamist militant leader born in Aleppo. He was instrumental in developing Hizb ut-Tahrir in the United Kingdom before leaving the group and heading to another Islamist organisation, Al-Muhajiroun, until its disbandment in 2004.

For several years, Bakri was one of the highest-profile Islamists based in London and was frequently quoted and interviewed in the UK media. In December 2004 he vowed that Muslims would give the West "a 9/11, day after day after day", if Western governments did not change their policies. He has been described as "closely linked to al-Qaeda"—having released prepared statements from Osama bin Laden after the 1998 United States embassy bombings—but also as the "Tottenham Ayatollah", "little more than a loudmouth", and "a figure of fun".

In 2005, following the 7 July 2005 London bombings, The Sunday Times reported that "a dozen members" of his group Al-Muhajiroun "have taken part in suicide bombings or have become close to Al-Qaeda and its support network". Shortly after, Bakri left the UK, where he had sheltered for 20 years, for Lebanon. While there, he was informed by the Home Office that he would not be allowed back into the UK.

Lebanon's state-run National News Agency said on 12 November 2010 that Bakri was among 54 people sentenced by a military court to life in prison with hard labour after being accused of acts of terrorism. After the decision, Bakri told reporters, he would "not spend one day in prison", and said, "I will not hand myself in to any court. I do not believe in the law in Britain as in Lebanon." On 14 November 2010, he was arrested by the Lebanese police and was transferred to Beirut. In October 2014, Bakri was sentenced to six years in prison with hard labour by a Lebanese court.

Released from prison in Lebanon on the 29th March 2023