With the rapid development of various new technologies, vehicles are equipped with new modules, new modes of charging, and more and more new functions, and the electromagnetic radiation environment of vehicles is gradually changing. Firstly, the test methods and test limits of electromagnetic field (EMF) item are compared and analyzed. The test results of EMF item in recent 5 years are analyzed statistically, and the key components affecting vehicle electromagnetic radiation safety are given. Through the analysis of the output power, layout and design mode of these key components, relevant optimization measures are proposed to improve the electromagnetic radiation safety performance of products, in order to provide guidance for the design and development of enterprises' products and the subsequent rectification and optimization.