Abstract: Infrared low-background detection technology is mainly used in space environment, the sensitivity of detection system has a gret relationship with the background radiation of detection system. How to effectively suppress the background radiation of detection system has always been the important research direction. And recognition has been a research hotspot in infrared field, adding the detection spectrum is the most effective way to get the features of target. An infrared multi-band detection technology based on optical lens local refrigeration and optical spiltter was introduced. Firstly, adopting the idea of integrated design with optical system and detector, integrate local optical system into the infrared detector and refrigeration with infrared FPA, then dividing the two lights by optical spiltter, which achieved dual-band ability, if the dual-band FPA was used in the future, the system can have the multi-band ability. Comparing the results of self-radiation under different optical types by the simulation of optical self-radiation, it can be seen that the background radiation of this technology is reduced to 1/4 of the ordinary temperature optical system, the sensitivity has also been greatly improved. This technology has obvious advantages and great potential.