In this thesis, a standard flow path is proposed to establish the model library for inductors and capacitors in multilayer substrate structure. By the way of excellent agreement between simulation and measurement within self resonant frequency ¡]SRF¡^, we aimed at the demanded performance of passives in modules and adopted Pi-section equivalent circuits as basic model. Meanwhile, an automatic program on CAD-based platform is used for extraction of Pi-model circuit elements and calculation of SRF, quality ¡]Q¡^factor and modeling errors. In the end, we contributed the methodology to have the best performance of embedded passives design in multilayer substrate structure and established a completed model library for inductors and capacitors embedded in low temperature co-fired ceramic¡]LTCC¡^substrate for the design need in implementation of RF modules.