As environmental problems caused by CO2 emissions have become serious, interest in CO2 processing technology has increased and is called carbon capture and storage (CCS). CO2 capture is the most energy consumed and occupies about 80% of the CCS process. Therefore, energy reduction using a new absorbent is inevitable. CO2 physical absorption method uses methanol as an absorbent, and it must be operated at a very low temperature (-40°C). Many studies are conducted to develop new absorbents that can operate at room temperature and reduce large freezing energy. In previous studies, Al2O3/methanol and SiO2/methanol nanofluids are developed, and their CO2 absorption performance has improved significantly. However, since nanofluids use solid particles, there are fatal problems such as tube clogging and sedimentation. To solve this problem, the nanoemulsion absorbents in which nano-sized oil droplets are dispersed in methanol instead of solid particles is developed and CO2 absorption performance is evaluated. When dodecane is added by 0.05 vol%, the CO2 absorption rate is improved by 10% compared to pure methanol. To use the absorbent for a long period, dispersion stability must be maintained. Dispersion stability of the nanoemulsion absorbents is evaluated by Tyndall effect, turbidity, and particle size analysis. As a result, it shows that dispersion stability is maintained at least 7 days. The structure of the nanoemulsion is visualized with a cryo transmission electron microscope. Based on this, dispersion mechanisms of the nanoemulsion absorbents is clarified. Thermal conductivity and viscosity of the nanoemulsion absorbents are measured. It shows 1%, 15% enhancement in thermal conductivity and viscosity, at the optimum conditions, respectively.