Rapid mobile communication technology development has brought tremendous convenience to society. With people's increasing hunger for the improvement of quality of life, the term body-centric wireless network has gradually entered everyone's vision. The so-called human body centre wireless network is a wireless network cantered on the human body. Various devices are interconnected through this wireless network with abundant functions. At the same time, in order not to cause inconvenience to users, these devices are generally divided functional modules, some of which are implanted into the human body, and some are wearable. Therefore, the application of the human body center wireless network will inevitably bring incredible changes to the medical, military equipment, personal identification, navigation, entertainment, and other industries. Compared with CT, MRI, and other traditional detection technologies, the wearable brain detection system based on microwave imaging technology is characterized by low cost and portability. In a microwave imaging system, antenna, as a front-end device for sending and receiving RF signals, is a key element, and its performance is crucial to the imaging effect. To make the imaging effect more obvious and the detection system more convenient to carry, the microwave stroke detection system puts forward requirements for the antenna: ultra-wideband, miniaturization, low profile, low-frequency band, and vertical or directional radiation. Meanwhile, the antenna should be able to achieve good conformation with the human brain, so the flexible antenna with vertical radiation or directional radiation should be designed to make the antenna have good bendability so that it can be more easily embedded into the wearable system. This paper is divided into four parts. First, the background of the microwave brain detection status is introduced. The second part describes the theoretical knowledge of the microstrip antenna, including the concept of microstrip antenna, type, feeding mode, and main electrical parameters of the antenna. The third part introduces the concrete method and step of the antenna design and analyzes the simulation image. The simulation software platform used in this project was developed by an American company. HFSS is a three-dimensional electromagnetic simulation software platform. The fourth part describes the brain structure and flexible materials, according to the real environment, design the antenna, and get performance simulation.