The current regional water supply and power generation structure is not able to achieve sustainable development in the long term. It is worth exploring whether the production, trade and the corresponding water footprint of the power sector in the Beijing-Tianjin-Hebei (BTH) region can meet the long-term development needs of the region after the dual-carbon goals is proposed. Therefore, this study constructed a dynamic multiregional computable general equilibrium model to simulate the changes in the production and trade of the power sector and its water footprint in the BTH region caused by the carbon reduction policy. Four carbon reduction scenarios were designed in the model to explore the impacts of policies such as carbon tax, investment and renewable energy subsidies. The results show that the carbon tax policy has the most significant water saving effect on power generation; The carbon reduction policy significantly increases the inter-regional flow of virtual water in the power trade; The complete water footprint of the power sector under various scenarios does not change much (less than 15%), in which the water footprint of the power sector in Beijing has the highest sensitivity to the carbon reduction policy. Therefore, the focus of water conservation in the power sector under the dual-carbon target should be on the trade chain, optimizing the trade structure and reducing interregional virtual water flows.