Measured equation of invariance (MEI) has been successfully used in many applications. It has been illustrated that the MEI is specially suitable for the decrease of computation time and computer memory space. However, for multiconduc-tor interconnects in multilayered dielectric media, the Green's function is complex and the integrals of Sommerfeld type are time consuming. In this paper, equivalent source and mea-sured equation of invariance (ES-MEI), a modification of the MEI, The node number is further decreased and the integrals of metron multiplied Green's function are avoided. It will be verified by several examples that the ES-MEI is very suitable for fast parameter extraction for mlticonductor interconnects in multilayered dielectric media.