Abu Bakar Ba'asyir (born 17 August 1938), also known as Abu Bakar Bashir, Abdus Somad, and Ustad Abu ("Teacher Abu") is an Indonesian Muslim cleric and leader of Jamaah Ansharut Tauhid and Jemaah Islamiyah.
He ran the Al-Mukmin boarding school in Ngruki, Sukoharjo Regency, Central Java, which he co-founded with Abdullah Sungkar in 1972. He was in exile in Malaysia for 17 years during the secular New Order administration of President Suharto resulting from various activities, including urging the implementation of Sharia law.