Abstract: Two rectangular resonant cavities with different anisotropic parameters are designed and investigated, which are filled partially with right-handed semiconductor metamaterial (RHSM) and left-handed semiconductor metamaterial (LHSM). The resonant mode solutions of the general case of the 3-D rectangular resonator cavities filled with non-dispersive RHSM and dispersive LHSM are explored by graphical method. It is demonstrated that the resonant modes in such resonant cavities are closely dependent on the spatial dispersion relation of the semiconductor metamaterial. Each resonant cavity including six subcases of different combinations of real and imaginary propagation constants of the two regions is discussed, and requirements of the geometry parameters to construct a resonant cavity of no ph