Electric　power　generation　utilizing　Liquid　natural　gas　(LNG)　cold　energy　is　a　major　research　direction.　The　normal　cold　energy　power　cycle:　the　independent　thermal　cycle　with　natural　gas　direct　expansion　and　the　close-loop　Rankin　cycle　have　the　lower　cold　energy　utilization　efficiency.　Many　efforts　have　been　dedicated　and　different　optimizing　processes　have　been　proposed　to　improve　it.　However,　no　any　cycle　optimizing　target　and　methods　were　given　in　published　paper　to　estimate　the　cycle　performance.　In　order　to　get　a　normal　method　to　optimize　the　cold　energy　power　cycle,　a　new　methodology　combining　the　energy　level　analysis　and　the　pinch　analysis,　a　so-called　T-Omega-H　(temperature-energy　level-enthalpy)　diagram,　was　proposed　to　analyze　the　optimizing　space　of　a　basic　Rankin　cycle.　The　results　showed　that　the　thermodynamic　imperfection　in　heat　exchanger　was　the　main　position　for　improvement.　Based　on　it,　a　cascading　power　cycle　with　LNG　cold　energy　recovery　was　proposed　and　its　performance　was　analyzed　by　proposed　method.　The　analytical　results　showed　that　the　cascading　cycle　has　a　higher　power　output　and　lower　specific　power　consumption　than　that　in　the　normal　cold　energy　power　cycle.　The　simulating　results　showed　that　this　new　method　is　effective　for　improving　the　power　generation　of　thermodynamic　cycle.