Abstract: A modeling approach for electromagnetic field coupling to a microstrip line connected with nonlinear component is proposed firstly. On this basis, a system-level analysis method of electromagnetic effects on an electronic system containing nonlinear components is presented. Nonlinear scattering parameters based on a black-box model are used to represent the nonlinear behavior of components, and can be extracted from measurement. Finally, the proposed method is experimentally validated by a laboratory system including a simple nonlinear component, which is constituted by the anti-paralleled HSMS-282C Schottky diodes pair welded to a 50 microstrip line. The calculated results using the proposed method show good agreements with the measured data.