Born in Kabal Tehsil, Swat, in 1954 Khan started out as a student activist of a left-wing secular party in the 1960s, but became a religious extremist in the early 1990s. He became the chief spokesman of the Swat Taliban in 2007.
In an interview with New England Foundation for the Arts, when asked about his usage of American-styled English and pronunciation, he revealed that he had lived for some time in Boston, Massachusetts. He had spent 4 years in the USA and worked as a painter in Boston. The BBC reported that Khan spoke Pashto, Urdu, English, Arabic and Persian, and had lived in or travelled across more than a dozen countries in the Middle East, Europe, the US and Asia.
In April 2009 he denounced any Pakistanis who disagreed with his interpretation of Islam calling them non-Muslims. It was also revealed due to a telephone intercept that Khan had urged attacks on the families of soldiers. "Strikes should be carried out on their homes so their kids get killed and then they'll realise". Before the start of the Army offensive against the Taliban, Khan claimed that his fighters controlled "more than 90 per cent" of Swat.
After the 2009 operation in Swat he was still at large, vowing that his men will step up attacks. However he was arrested on 10 September by the security forces of Pakistan  in the suburbs of Mingora.
He was one of eight men sentenced to death by a military court on 28 December 2016 for terrorism and other offences. Khan's appeal before the Peshawar High Court was weakened following the Supreme Court's decision in Said Zaman Khan v. Federation of Pakistan. His sentence was briefly stayed by the High Court on 24 May 2017, on the basis of a petition filed by his wife.
- "Pakistan to hang 'butcher of Swat' Muslim Khan". BBC. 2016-12-29. Retrieved 2017-02-04.
- Interview with Haji Muslim Khan: Part II April 27, 2009 (PDF). The NEFA Foundation. 2009-04-27. p. 3. Archived from the original (PDF) on October 4, 2012. Retrieved 2009-08-24.
I lived in Boston, Massachusetts, United States, a foreigner there.
- Watson, Ivan (2009-05-14). "Taliban: All local leaders must quit". CNN. Retrieved 2009-09-11.
In an earlier phone interview with CNN, he described how he had spent four years living in the United States, working as a painter in the Boston, Massachusetts, area.
- TTP says Osama welcome in Swat: Taliban reject peace accord
- Taliban recruits teenage suicide bombers for revenge attacks
- Pakistan war planes bomb Taliban hide-outs
- Swat Taliban vow attacks after Ramzan
- TTP spokesman Muslim Khan arrestedDawn Pakistan
- Pakistan: Swat Taliban spokesman, 4 others held
- "General Bajwa signs black warrants of 8 terrorists - Pakistan - Dunya News". dunyanews.tv. Retrieved 2016-12-28.
- Shah, Waseem Ahmad (29 May 2017). "'Brief respite' for former Swat Taliban spokesman". Dawn. Dawn Group. Retrieved 27 August 2017.