Ultraviolet photodetectors (UV PDs) are pivotal in a myriad of applications, including optoelectronics, medicine, and environmental monitoring. This study explores the enhancement of GaN-based narrowband UV PDs through the integration of cost-effective colloidal silver nanowires (Ag NWs) and gold nanoparticles (Au NPs). We investigate the synergistic effects of these plasmonic nanostructures on the photoresponse of GaN PDs, a topic previously underexplored. Our findings reveal that a sparse surface coverage with Ag NWs (∼3 %) significantly boosts the photoresponse by up to 11.5 times compared to non-decorated PDs. However, increased NW density leads to diminished enhancement due to GaN layer shading, as supported by numerical modeling. Further augmentation is achieved by incorporating Au NPs, resulting in a photoresponse increase of up to 22.3 times. The optimal configurations exhibit responsivities of 42.6 AW-1 and 57.3 AW-1 for samples with sparse Ag NWs and dense Au NPs, respectively, outperforming previously reported GaN-based hybrid UV PDs. This research underscores the potential of hybrid semiconductor-metal structures in developing highly sensitive, narrowband UV photodetectors, leveraging the tunable plasmonic properties of Ag NWs and Au NPs. Our approach offers a promising pathway for advancing UV PD technology through feasible and scalable fabrication methods.