Abstract: Infrared early warning satellites are an important part of anti-missile early warning systems. Compared to ground-based radar early warning systems, infrared systems have significant advantages in terms of rapid response, space coverage, and anti-clutter interference. Taking those of the United States as examples, early warning satellite systems are divided into equipment and experimental satellite systems. The development history and current state of international infrared early warning satellite systems and payloads are introduced in detail, and the developmental trends of space-based payloads are analyzed. According to the requirements and challenges of space-based early warning, several necessary capabilities requiring consideration in the development of infrared early warning satellite systems and payloads are discussed.