To deal with the issues of energy consumption for Network on chip(No C), this paper proposes a method for partitioning an No C architecture into multiple voltage-frequency islands to achieve low energy consumption. The method considers the number of Voltagefrequency islands(VFIs), delay and reliability as multiconstraints. A mathematical model for Integer linear program(ILP) algorithm is constructed and LPSolve is used to solve the issues of VFI partition. The validity of the VFI partition method is accurately verified for E3 S and MMS.Simulation results show that the proposed method is more reasonable and smaller consumption can be a chieved while multi-constraints are met. This method can get less energy consumption from 33.6 % to 9.1% or 16.7% than those by the other methods. To deal with the issues of energy consumption for Network on chip (No C), this paper proposes a method for partitioning an No C architecture into multiple voltage-frequency islands to achieve low energy consumption. The method considers the number of Voltagefrequency islands (VFIs ), delay and reliability as multiconstraints. A mathematical model for Integer linear program (ILP) algorithm is constructed and LPSolve is used to solve the issues of VFI partition. The validity of the VFI partition method is accurately verified for E3 S and MMS.Simulation results show that the proposed method is more reasonable and smaller consumption can be a chieved while multi-constraints are met. This method can get less energy consumption from 33.6% to 9.1% or 16.7% than those by the other methods.