Surface plasmon-based devices exhibit exceptional light confinement and enhanced light-matter interactions at subwavelength scales， offering a promising route to overcome the diffraction limit and enabling breakthroughs in nanophotonics and optoelectronic integration. Chemically synthesized noble metal nanoparticles， with their intrinsic subwavelength dimensions and outstanding plasmonic properties， have emerged as ideal building blocks for high-performance surface plasmon devices. To realize this potential， high-throughput， cost-effective， and structurally controllable self-assembly strategies are essential. This review focuses on DNA-directed assembly approaches， highlighting their applications in constructing strongly coupled， nonlinear， and low-loss plasmonic devices. Based on the fundamental physical processes of surface plasmons， we emphasize how the structural precision and programmability of DNA molecules empower optical phenomena， aiming to establish a new paradigm for the precise construction of advanced nanophotonic devices using biological macromolecules. Finally， this review summarizes the key challenges currently faced by self-assembled photonic devices， including cross-scale fabrication， structural defects， and loss control， and， on this basis， proposes future key research directions and feasible solutions. DNA-directed assembly demonstrate broad prospects in the development of high-performance and multifunctional plasmonic structures and devices， with potential applications in optical communication， quantum information， artificial intelligence and disease detection.
