This article deals with the model development for a single walled carbon nanotube (SWCNT) piezoresistive sensor at system level design. The framework of VHDL- AMS is used for implementation and simulation, consisting of compact submodels that describe components performing heterogeneous functions. The SWCNT mechanical and electrical compact models presented in the article are based on the analytical model, lumped element model and the simulation results based on density functional theory (DFT). The macromodels of the MEMS are built using a reduced order modeling technique based on finite element simulations. This article presents and discusses the most important aspects of the development of system models and essential model parameters.