Abstract: Radar electronic equipment such as transmitter and receiver (T/R) modules could be interfered or damaged, because of the couplings through the front-door and the back-door from the tough electromagnetic pulses which have the characteristics of high peak power, wide spectrum range, and high energy. Even the whole radar system could be destroyed due to this harsh electromagnetic environment. So, step by step electromagnetic protections for radar system are proposed by systems, components and devices in this paper. A new type of radome with tough electromagnetic protection can be made by using new materials and new methods such as plasma, frequency selective surfaces, energy selective surfaces, cascaded energy and frequency selective surfaces and electromagnetic cloak. Some materials and devices, including electromagnetic shielding materials, wave absorbing materials, filters, photoelectric converters, surge suppressors are used in T/R modules to prevent electromagnetic interference. An intelligent electromagnetic protection system can be established, so that the radar has the ability to adapt to complex electromagnetic environments automatically by using a specific time-domain and frequency-domain radar system design, and using some other technologies such as electromagnetic interference cancellation, evolutionary hardware.