Solid composite electrolytes that integrate metal–organic frameworks (MOFs) with polymer electrolytes combine the flexibility of polymers with structural order and rigidity of MOFs, emerging as promising candidates for high-performance solid-state lithium batteries. However, conventional physical blending leads to poor interfacial compatibility between MOFs and polymer, hindering ion transport and resulting in phase separation during processing and operation, thereby compromising structural integrity and compositional homogeneity. Electrospinning has recently offered an effective strategy to better incorporate MOFs within polymer matrices, enabling more uniform composites and enhanced ion conduction. Based on these developments, this review systematically elaborates on the component design and ion transport mechanisms of MOFs/polymer nanofiber electrolytes, with a focus on advanced integration strategies beyond physical mixing. This review further discusses combined methods for fabricating MOFs/polymer nanofiber electrolytes and examines the synergistic mechanisms by which MOFs and polymers collectively enhance ionic conductivity and interfacial stability. This review also provides a detailed analysis of current challenges facing MOFs-based composite electrolytes and proposes potential future research directions. By presenting a comprehensive, systematic, and accessible overview of integration strategies and functional mechanisms in diverse MOFs/polymer nanofiber electrolytes, this review aims to inform and inspire the development of high-performance solid-state lithium batteries.