To address the challenges in LNG cold energy utilization and waste heat recovery from gas turbine flue gas, and to facilitate the liquefaction of the contained carbon dioxide, a novel combined cooling, heating and power (CCHP) system is proposed. The effects of the split ratio (x), the compressor inlet pressure（p₂₅),and the mass fraction of carbon tetrafluoride in the mixed working fluid (w) were analyzed. A multi?objective optimization was subsequently performed using a genetic algorithm. The results show that decreasing x and increasing w enhances thermal efficiency, exergy efficiency,and net output work,while reducing the average unit cost.The optimal compressor inlet pressure (p₂₅) was found to be in the range of 8.0 MPa to 9.0 MPa. The thermal efficiency, exergy efficiency, the average unit cost and the average unit cost under the optimal working conditions of the system were 67.62%, 56.98% and 22.11 $/GJ，respectively.