A fully hybrid computer-aided circuit design to achieve a first-pass on-board CMOS LNA fabrication was studied and investigated. The LNA was implemented in 0.13-μm CMOS process. A post-layout die-level electromagnetic-field analysis, to extract the interconnection and interaction parasitic between on-chip components, was used. The extracted touchstone model was integrated with circuit model of board including the microstrip lines and surface mounted passive elements as well as the electromagnetic field extracted model of radio-frequency coaxial connectors. The hybrid electromagnetic-circuit simulation results are compared with the measurement results for evaluation. The comparison presented an excellent correlation between the simulated and measured results. The connector’s effects can be de-embedded using its developed electromagnetic model. This method of simulation and optimization is targeted to achieve first-pass run instead of optimization using costly prototypes.