Abstract: With the rapid development of computational electromagnetism and computer technology, electromagnetic computing plays an important role in radar design. This paper introduces the application of electromagnetic computing in radar design, including radar antenna design, feeder and microwave network design, radome design and performance evaluation of radar antenna in complex electromagnetic environment. Three common methods of full wave electromagnetic simulation, such as finite element method, moment method and time domain finite difference method, and high frequency approximation are introduced. Finally, the new requirements for electromagnetic computing in radar technology are given.