Ömerli, Şanlıurfa, Turkey
|Allegiance||Kurdistan Workers' Party (PKK)|
|Years of service||1978-2004|
|Rank||Military commander in Iraqi Kurdistan|
The younger brother of Abdullah Öcalan, Osman studied at teachers’ training college before joining the PKK when it was founded in 1978 and spending two years in Libya. He joined the central committee in 1986, and the executive committee in the 1990s, becoming virtually second in command of the PKK, but in 1992 he suffered disgrace after signing a truce with the two main Iraqi Kurdish parties, the KDP and the PUK, and was jailed by the PKK.
"In June 1993, they removed all my powers," he told The Middle East in an interview. "I was isolated in a cell for three months and interrogated for 52 days before being tried in February 1995. The trial lasted only one day.I was warned that if I continued to defend my ideas, I would be executed. If not, I would be pardoned. A lawyer? Out of the question. The trial was conducted under the law of the mountain." 
In 1994, he left the PKK in order to marry a fellow PKK fighter. The PKK forbids relationships between its guerillas. He later rejoined the PKK. In 2000 the Independent referred to him as a "senior commander" of the PKK when Medya TV, the underground Kurdish satellite television channel reported him as claiming that the Turkish authorities wanted his brother to die. 
In March 2003, in an interview to western journalists from his refuge in the Qandil mountains, he asserted "We will never allow ourselves to be disarmed as long as the Kurdish issue is not settled." 
He split away from the PKK again in August 2004 to form the Patriotic Democratic Party (PWD), with Hikmet Fidan to challenge Murat Karayılan.  After Fidan's assassination the PWD merged with the HADEP.
In November 2007, in an interview in Arbil, he claimed that the PKK were retreating from Iraq into Iran. He estimated the total strength of the PKK guerrillas at just under 7,000. "There are 2,750 fighters in Turkey," he said. "A further 2,500 are in the border areas of Iraq and 1,500 are in Iran ... In the last six months the PKK has started a war against Iran."  Speaking from his home in Koya in Iraqi Kurdistan, he claimed that Turkey was denying medical treatment to his brother Abdullah Ocalan and warned that suicide bombers would strike Turkish cities if he died in prison.   Today's Zaman, referring to him as a "former PKK leader," quoted him as saying "For 20 years I was part of the struggle; but because of ideological differences, I pulled out of it. Now I am with armed fighters who defend themselves, but am against the PKK." 
- "Kurdistan Turkey: PKK dissidents accuse Abdullah Ocalan". Middle East Magazine. July 2005. Retrieved 2009-08-18.
- Huggler, Justin (2000-05-23). "Turkey is accused of 'ignoring ill' Ocalan". London: The Independent. Retrieved 2009-08-18.
- Strauss, Julius (2003-03-08). "Kurdish rebels ready to fight to the death for their cause". London: Daily Telegraph. Retrieved 2009-08-18.
- "Can the PKK renounce violence?". Middle East Quarterly. 2007. Retrieved 2009-08-18.
- "Former leader of Kurd rebels reveals retreat into Iran". London: The Independent. 2007-11-05. Retrieved 2009-08-18.
- "Osman Ocalan: Turk cities will pay if PKK leader dies in jail". Kurd Net. 2007-11-11. Retrieved 2009-08-18.
- "Ex-leader: rebel Kurds have left Iraq". AP News. 2007-11-30. Retrieved 2009-08-18.
- "Osman Öcalan says PKK camps in N. Iraq taken over by PJAK". Today's Zaman. 2007-12-01. Retrieved 2009-08-18.
- "Öcalan's unofficial Ergenekon testimony". Hurriyet. 2009-08-07. Retrieved 2009-08-18.