高熵合金突破了传统溶剂-溶质合金设计范式，为解决金属材料长期存在的强度-塑性矛盾提供了新的材料体系。然而，目前关于高熵合金强韧化的研究大多聚焦于具体组织特征或强化现象，缺乏能够贯穿成分设计、组织调控和变形机制的统一理论框架。本文结合作者团队近年来的系列研究成果，提出并系统阐述熵-焓协同组织调控与强韧化理论。该理论认为，高熵合金的强韧化本质上来源于构型熵与混合焓共同决定的多尺度组织结构及其协同变形机制。基于这一认识，建立了成分设计-组织构筑-变形响应-强韧化效果的统一逻辑链条，并从原子尺度局域化学有序、纳米尺度共格析出、微米尺度亚稳相变以及多尺度组织协同四个层面系统总结高熵合金的强韧化规律。进一步结合典型实例，阐明高熵合金与传统合金强韧化机制的共性与差异，提出高熵合金强韧化设计的普适模型。

High-entropy alloys (HEAs) have transcended the conventional solute–solvent alloy design paradigm and emerged as a promising materials platform to overcome the long-standing strength–ductility tradeoff in metallic materials. However, current studies on the strengthening and toughening of HEAs primarily focus on specific microstructural features or individual strengthening mechanisms, lacking a unified theoretical framework integrating alloy composition design, microstructural evolution, and deformation mechanisms. Based on a series of recent studies conducted by the authors and their collaborators, this study proposes and systematically develops the theory of entropy–enthalpy synergistic strengthening and toughening. This theory postulates that the superior mechanical performance of HEAs originates from their multiscale microstructures and cooperative deformation mechanisms, jointly governed by configurational entropy and chemical enthalpy. Building on this concept, a unified framework linking alloy composition design, microstructure development, deformation response, and strengthening–toughening performance is established. From the perspectives of atomic-scale local chemical ordering, nanoscale coherent precipitation, microscale metastability-induced phase transformation, and multiscale microstructural synergy, the strengthening and toughening mechanisms of HEAs are systematically summarized. Representative examples are further discussed to elucidate the similarities and distinctions between the strengthening–toughening mechanisms of HEAs and conventional alloys, thereby establishing a generalized design model for HEA strengthening and toughening.