The present study mainly deals with the preparation of Cu nanoparticles utilizing Cocinia grandis flower extract. Here the flower extract acts as a reducing agent in the formation of Cu nanoparticles. The flower extract reduces the metal ion into metallic nanoparticles and help in the reduction process. A peak appears at 600 nm (UV spectra), establish the formation CuNPs. The synthesized NPs are analyzed using various techniques. As-synthesized CuNPs is utilized as a catalyst for the reduction of noxious nitrocompound.