The guidance and support from market mechanisms and relevant policies play an important role in the sustainable development of low-carbon power system. The basic types of electricity markets and specific characteristics of integrated nodal market mode are discussed. The main issues to be resolved in low-carbon electricity design are analyzed from perspectives of gird-integration code, pricing mechanisms, generation capacity, and infrastructure investment. Based on the objective requirement of green power generation integration for low-carbon electricity design, the four key issues of low-carbon technology options, system operation, power supply reliability, and infrastructure investment in low-carbon electricity design are studied. Finally, relevant policies are analyzed for issues including carbon reduction caps, grid-integration standards, environmental-friendly power scheduling, long-term price protection, and transmission investment. The interactive relationship between market mechanisms and low-carbon electricity policy is hence revealed.