Abstract: The Design capability of nonlinear layout algorithm in plat mode is far behind the pace of integrated circuit design development,a clustering algorithm used for VLSI(Very-Large-Scale Integration) nonlinear placement is proposed reducing the circuit size and complexity in order to improve the speed and optimize the quality.The new cluster technique takes the ratio of internal and external connection degrees of two cells into account.And,it adds the area constraints to balance every cluster.It has been embodied into a nonlinear placement algorithm.The clustering based placement run-time explicitly decreases by 40%and the quality improves by 12%compared to the flatten mode.The half-perimeter wire-length of the placer after detailed placement outperforms current state-of-the-art placers Capo,FastPlace,Fengshui and mPL5-fast by 7%,9%,7%,and 5% respectively.