The postharvest life of the flower of endangered orchid species (Rhynchostylis retusa) was examined with different treatments of vase solution consisting of different concentrations of silver and copper nanoparticles (AgNPs and CuNPs), and equal doses of sucrose (6%). The experiment was performed in the Horticulture Laboratory, Assam Agricultural University, Jorhat (Assam) during 2020-2022. During experimentation, it was observed that the treatments with AgNPs and CuNPs substantially improved all the vase life characteristics of foxtail orchid flowers, compared to the untreated control. T3 (AgNPs 20% + 6% sucrose) treatment was found to gain maximum RFW (124.17%) and water uptake (14.67 ml/day). Likewise, maximum retention of carbohydrates (57.92 mg/100ml), TSS (10.86%), and MSI (60.72%) at the end of the experiment were recorded in T3. Furthermore, T3 strongly inhibited the microbial counts (7.12 Log 1₀ CFU ml/L) in the vase solution and extended the average days to flower fading (4.85 days) and vase life (10.85 days) respectively. For all the parameters recorded, treatment T5 (AgNPs 30% + 6% sucrose) remained the second-best treatment among all the treatments followed by T7 (CuNPs 20% + 6% sucrose). Thus, nanoparticles can be successfully used to extend the vase life of foxtail orchid flowers.