In this paper, we presented two types of ferrite&si double layer substrate microstrip lines structures and derived waveguide admittance through coordinate rotation and Fourier transformation of Maxwell equations, then we analyzed its characteristics. We performed dispersion characteristic calculations on microstrip lines, discussed influence of various parameters of microstrip lines on dispersion characteristics and compared their characteristics, then we discovered parameters influence on one specific type of structure dispersion is minimum, especially on technique dimension of dielectric. It can make applications for IC fabrication.