To address the influence of multi-scale complex loads on the deep-sea mining transport system during operations, the Failure Modes and Effects Analysis (FMEA) method is improved based on the α-cut fuzzy numbers, resulting in an α-cut based Fuzzy FMEA model ( α-FFMEA). The evaluation criteria of failure modes, including occurrence ( O), severity ( S), and detectability ( D), are described by using linguistic terms, effectively overcoming the limitations of traditional methods in dealing with uncertainty. Analytic Hierarchy Process (AHP) and entropy theory are used to assign the weights of O, S, and D reasonably and objectively, ensuring the scientificity and accuracy of the risk assessment. The α-cut fuzzy numbers and centroid method are then used to calculate the risk priority number of each failure mode across different α-cuts, providing a quantitative basis for system failure prevention and optimization. Finally, the transport system in the deep-sea linkage system is analyzed to validate the effectiveness and applicability of the model, offering important theoretical basis and practical guidance for the optimization and failure prevention of the deep-sea mining transport system.