The invention relates to the technical field of infrared radiation, in particular to a device for enhancing the infrared radiation characteristic of a space target. The device aims at solving the problems that an existing infrared radiation enhancing device is large in size and prone to leading the surface temperature of the space target to be too high. The device is characterized in that the device comprises a heat control taper sleeve (1), an electric heating sheet (2) and an air barrier layer (3), wherein the heat control taper sleeve (1) is fixedly connected to the outer surface of a space target shell (4); the electric heating sheet (2) is fixedly connected to the interior of the heat control taper sleeve (1); the air barrier layer (3) is located between the heat control taper sleeve (1) and the space target shell (4); the heat control taper sleeve (1) is used for improving the infrared radiation characteristic of the space target after the temperature rises; the electric heating sheet (2) is used for heating the heat control taper sleeve (1); the air barrier layer (3) is used for realizing heat isolation between the heat control taper sleeve (1) and the space target shell (4) so that the temperature of the space target shell (4) can not be too high. The device has the advantages of the simple structure and high reliability.