 Low-dimensional nanomaterials are widely investigated in infrared photodetectors, PDs, due to their excellent optical and electrical properties. To further improve the PDs' property like quantum efficiency, metallic microstructures are commonly used, which could squeeze light into sub-defraction volumes for enhanced absorption through surface plasma exciton resonance effects. In recent years, Plasmonic-enhanced nanocrystal infrared PDs have shown excellent performance and attracted much research interest. In this paper, we summarize the progress in Plasmonic-enhanced nanocrystal infrared PDs based on different metallic structures. We also discuss challenges and prospects in this field. This article was authored by Naichu and Yen, Yen-Yen Cho, Shubing He and others.