In the present work, Zn, Cu monometallic and bimetallic nanoparticles were synthesized using leaves extract of Borassus flabellifer. Plant extract acts as both surfactant and reducing agent. The synthesized nanoparticles were characterised by UV-Vis, XRD, FESEM, EDX, and HRTEM techniques. UV-Vis spectroscopy is used to monitor the synthesis of nanoparticles. XRD technique was used to confirm the amorphous nature of nanoparticles. The FESEM images demonstrate that the shape of the nanoparticles such as Zn monometallic (pseudo-spherical), Cu monometallic (rod), Zn-Cu bimetallic are (pseudo-spherical and rod-shaped). HRTEM images show the approximate size of the Zn, Cu monometallic and Zn-Cu bimetallic nanoparticles is 3.0 nm, 3.52 nm and 2.2 nm respectively. EDX spectra confirm the presence of Zn, Cu and O in the sample. Synthesized Zn, Cu monometallic nanoparticles, and Zn-Cu bimetallic nanoparticles were used to evaluate their possible antimicrobial, antidiabetic and antioxidant properties. Bimetallic nanoparticles displayed higher antioxidant, antidiabetic, and antimicrobial properties in the comparison of monometallic nanoparticles. The results suggest that Zn-Cu bimetallic nanoparticles have greater potential than monometallic nanoparticles.