A new route for the formation of osmium nanoparticles (NPs) having different morphologies like aggregated clusters, chain-like networks, and small spheres are reported. The synthesis was done by utilizing a simple wet-chemical method at room temperature (RT) by the reaction of OsO 4 , cetyl trimethyl ammonium bromide (CTAB), 2,7-dihydroxynaphthalene (2,7-DHN) and NaOH under 30 min of reaction. The diameter of the individual particles in all the morphologies was B1-3 nm. The synthesized materials have been tested for catalysis and SERS studies. The catalysis study was examined taking different organic nitro compounds and the catalysis rate was found superior as compared to other reports. The surface enhanced Raman scattering (SERS) study was done taking Rose Bengal (R Be) as a probe molecule and the observed enhancement factor (EF) value was found superior or comparable to most of other noble metal NPs. The overall synthesis process was simple, less time consuming and cost-effective. The enhanced catalytic and SERS activities of the Os NCs might open up a new avenue for the application in other organic catalysis reactions, SERS based detection of environmentally important trace bio-molecules and sensors.