With influences of interconnect inductance,thermal-electric coupling effects and interconnect temperature distribution,a delay optimized method by repeater insertion is presented.A interconnect resistance model and a delay model are obtained respectively based on interconnect temperature distribution.The repeater insertion optimal delay is calculated considering electro-thermal coupling among power,delay and temperature.Optimized results are successfully obtained with Matlab software.Repeater insertion in 45 nm technology is simulated.It shows effectiveness of the method.In addition,it indicates that the optimal delay is overestimated without inductance effect.Optimal delay is underestimated without consideration of temperature distribution.As overestimated global interconnect width is 245nm,8.71% optimal delay can be underestimated without considering temperature distribution effect.