In order to effectively utilize LNG(liquefied natural gas) cold energy and liquefy CO₂ in gas turbine exhaust gas, a new process of LNG cold energy to liquefy CO₂ and CO₂ power cycle was proposed. In this process, Reheat cycle and regenerative cycle were added on the basis of conventional Rankine cycle, and multi-flow strand heat exchanger was set up. Chemical process simulation software was used to simulate the process flow and sensitivity analysis of reflux temperature, interstage cooling temperature and maximum circulating temperature and pressure was carried out to obtain the best operating parameters. Exergy efficiency, specific work and CO₂ liquefaction rate of the system were analyzed and calculated by exergy analysis. Exergy efficiency of exergy was 54.16%, specific work was 335.9 kJ/kg LNG, and CO₂ liquefaction rate was 0.621 7 kg/kg LNG in a new process. The evaluation indexes of the new process were better than those of the existing process. As for the exergic efficiency, exergic efficiency of exergic was as the highest and the temperature of CO₂ after liquefied was as the constraint condition, exergic efficiency of exergic was 54.28% and specific power was 337.5 kJ/kg LNG, so the system performance was further improved.