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Nowadays reusability of LREs, represented in projects such as Callisto and Ma?a (both including the re-usable Prometheus engine), is seen not only as essential in the effort to prepare competitive future European space access, but also sets a new requirement towards high reliability engineering standards. With engine operation life in excess of a single mission, it is necessary to evaluate the most critical components, which could develop cracks as in case of the e.g. the turbopump turbine BLISK (Blade Integrated Disk) and, as a result, lower the total engine flight live [1, 2]. Within our research we focus on the turbine blade analysis for reusable LRE applications including high cycle fatigue (HCF) and low cycle fatigue (LCF). Turbine blades are subjected to large thermo-mechanical cyclic strains arising from high temperatures driving gas in combination with a fast start-up sequence as well as high rotational speed crucial for obtaining high performance and structural mass efficiency for LREs. Therefore, in addition to bending torsion as well as thermal gradient and centrifugal forces, it is decisive in durability studies to account for creep effects [3, 4, 5, 6]. To predict the turbine blade fatigue life, we compare the analytical (0-D) and numerical approach for a selected test case. The fatigue life analysis evaluates the BLISK at the highest loading condition accounting for HCF along with a Coffin-Manson based approach for the LCF contribution. Each operational cycle under constant maximum loading condition is applied to study the creep effect. As a result, an enhanced fatigue life prediction method including both creep and fatigue conditions for a turbine blade is obtained. Key words: BLISK, Coffin-Manson, Creep, Fatigue Life Analysis, Finite Element Analysis (FEA) High Cycle Fatigue (HCF), Liquid Rocket Engines (LRE), Low Cycle Fatigue (LCF), Reusability, Reusable Launch Vehicle (RLV), Sustainability, Turbine Blade, Turbopump.