<p>Perovskite photodetectors (PDs) have attracted significant attention in the field of PDs due to the high responsivity (R) and external quantum efficiency (EQE). However, their instability still limits further development and applications. To enhance the stability of perovskite PDs, we have developed high-performance bulk heterojunction (BHJ) perovskite PDs by introducing highly stable Au nanoparticles (NPs) of different sizes into CH₃NH₃PbI₃: PC₆₁BM, leveraging localized surface plasmon resonance (LSPR) effects. This is ·primarily attributed to the incorporation of Au NPs, which not only enhances the light absorption ability of the device, but also modify the morphology and crystal quality of the perovskite film, thereby enhancing the performance of PDs through LSPR effect. Notably, compared with the non-sputtered Au NPs photodetector, the R of BHJ CH₃NH₃PbI₃: BC₆₁BM Au NPs photodetector increased from 0.018 to 0.825 A/W at 760 nm and the external quantum efficiency (EQE) increased from 3.510% to 221.128%. The research results indicate that Au NPs play a crucial role in LSPR-induced BHJ PD. Therefore, BHJ CH₃NH₃PbI₃: PC₆₁BM PD is expected to become a candidate material for the next generation of sensing and communication due to LSPR.</p>