To improve the infrared radiation intensity of KNO₃/Mg-Al decoy, the combustion and infrared radiation characteristics of the decoy were experimentally studied via the method of adding boron powder in the decoy by a far infrared thermal imager. Results show that the mass burning rate, combustion temperature and radiation radiance of the decoy increase by adding boron powder. With the content of boron powder increases from 0% to 2%, the mass burning rate of the decoy increaseing from 0.390 g·s^-1 to 0.564 g·s^-1. When the content of boron powder increases from 0% to 4%, the combustion temperature and radiation radiance increase from 727.71 ℃, 995.68 W·m^-2·sr^-1 to 1046.19 ℃, 1681.59 W·m^-2·sr^-1 respectively. With increasing the content of boron powder, the radiation intensity reveals the trend to increase firstly and then decrease. When the content of boron powder is 4%, the radiation intensity increases to the maximum of 2.64 W·sr^-1, revealing that adding a certain proportion of boron powder can effectively improve the mass burning rate, combustion temperature and infrared radiation characteristics of the decoy.