With the development of optoelectronic imaging technology, remote sensing optical system gradually develops towards super large imaging field of view in order to obtain target characteristic information in a wider space. Concentric multiscale system is a new type of large field of view optical system. At present, most of the schemes studied are multiscale system based on concentric spherical lens. Due to the limitation of optical materials, this optical system is generally only used in visible and near infrared optical bands, and is difficult to be applied in long-wave infrared band. Starting from the structure principle of concentric multi-scale system and considering the application of long-wave infrared band, this paper proposes to use spherical reflector instead of concentric spherical lens to construct a retracted multi-scale system based on spherical reflector. The system can achieve all the features of multi-scale system and can be applied in the infrared band. According to the construction principle of the system and the design idea of off-axis deviation field, a multi-scale system based on spherical reflector is designed. The main parameters of the single channel of the system are: the focal length is 72mm, the system F#=2, the working band is 8-12um, and the imaging field of view is 20 degrees x0.1 degrees. The imaging quality of the system is close to the diffraction limit in the full field of view, and the distortion of the full field of view is less than 5%. The circular field of view imaging of 360 degrees x0.1 degrees can be achieved by extending the spherical reflector and multi-channel splicing.