Selim Sadak was born in İdil and graduated from the Mathematics department of Diyarbakır Eğitim Enstitüsü.
[1] In the 1991 Turkey Parliamentary general election, he joined Leyla Zana, Mahmut Alınak, Hatip Dicle, Orhan Doğan, Ahmet Türk, Sırrı Sakık and Sedat Yurtdaş in the Social Democratic Populist Party (SHP) and was elected as the member of parliament for Şırnak in the 19th Parliament of Turkey.
In March 1994, the parliamentary immunity was lifted from Selim Sadak, Orhan Dogan, Hatip Dicle and Leyla Zana.
[8] In 2010 he was dismissed by the Interior Ministry as Mayor of Siirt after a sentence of 10 months imprisonment from 2008 got confirmed, a decision he objected.
[12] On 7 October 2011 he was sentenced in Diyarbakir court to one year and eight months prison for terrorist propaganda in relation to a speech that he made in 2007.