CCS technology can massively reduce the CO2 emissions of power plants and during industrial productions through technical phases as capture, transportation and storage. It is an alternative and effective measure for slowing down climate change. However, all the technological phases may have some impact on environment. The CO2 leaked in the transportation and storage phases may, if in a large quantity, cause irreversible ecological disaster. The purpose of studying the environmental tort liability of CCS project is to minimize the impact of CCS on the environment through legal regulation and to slow down climate change with CCS technology with the minimum social cost, which is also the most complicated aspect in the legal questions related to CCS at present. The study found that judges need to balance the public interests brought by CCS slowing down climate change and the personal interests of the party involved damaged by the leaked CO2 under common law system of the United States. In China, if the environment is polluted by the leaked CO2 in the CCS project, there are many uncertainties in tort liability except for the doctrine of liability fixation and the distribution of burden of proof. Once an accident of CO2 leakage happened, it is still hard for the party involved to obtain compensation for damages by tort lawsuits.