According to the theoretical methods and the situation investigated, the development and main application fields of infrared detection technology are presented. After analyzing the infrared radiation of stealth aircrafts, the tail nozzle radiation, tail flame radiation and skin heat radiation of stealth aircrafts are studied. Then, a specific infrared stealth method is given for each kind of radiation. Finally, a conclusion is given and more advanced infrared detection means against infrared stealth technologies are expected to satisfy the demands of modern military.