Elastomers have been recently proposed to integrate CO2 as carbon feedstock. These elastomers are produced by reacting carbon dioxide with propylene oxide and maleic anhydride. The resulting cross-linkable polyether carbonate polyols can be combined with isocyanates to form a novel class of polymers: CO2-based rubbers. These CO2-based rubbers are able to substitute conventional rubbers in synthetic elastomer products, such as sealants or flexible tubes. In this work, we present the first Life Cycle Assessment for CO2-based rubbers. To compare CO2-based and conventional rubbers our assessment considers all relevant life cycle stages from cradle-to-grave. The production system of CO2-based rubbers encompasses a nearby ammonia plant as a CO2 source, the conversion of CO2 to polyols, the reaction of polyols with isocyanates and finally, the incineration of CO2-based rubbers. Our analysis shows that CO2-based rubbers containing approx. 20% wt. CO2 have a global warming impact of 4.93 kg CO2-eq. Thus, CO2-based rubbers are no carbon sink. However, CO2-based rubbers reduce global warming impact by up to 34% if they substitute, for example, hydrogenated nitrile butadiene rubber on an equal mass basis. Fossil resource depletion is reduced by up to 33%. In contrast, other impact categories like ionizing radiation are increased by the utilization of CO2-based rubbers in some cases. Thus, our study indicates that CO2-based rubbers provide a promising pathway to reduce global warming impact and fossil resource depletion. However, it is likely that some other environmental impact categories such as ionizing radiation and freshwater eutrophication are increased.