The Altyn Tagh Mountain is the main area where the Precambrianbasements of Tarim craton are exposed. There are two ophiolitic belts in Altyn Tagh: one belt is exposed in the northern margin of Altyn Tagh whose formation age is about (829±60) Ma, the other is situated along the southern margin of Altyn Tagh and has a formation age of about (1449±270) Ma. This paper proposes a simple tectonic model for the Precambrian basement of Tarim craton established from ophiolites in Altyn Tagh area. The south Tarim block had amalgamated with Qaidam block during about 1400-1500 Ma along the present Altyn fault, while the south Tarim-Qaidam united block was still separated from the north Tarim block by an ocean. The united block of south Tarim and Qaidam collided with north Tarim block along the zone of high positive anomaly of central Tarim, Hongliugou and Lapeiquan in about 800 Ma. So since the Sinian (beginning at 800 Ma) there has been an integrated basement for Tarim craton.