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Silver nanoparticles/nanocomposites are gaining popularity for their unique features and wide-range of applications including bactericidal behaviour, sensing, and photocatalysis. In this report, a novel, single-step, sustainable, and low-cost fabrication of silver carbon quantum dots (Ag/CQDs) nanocomposites by using coal-derived carbon quantum dots (CQDs)as a reductant as well as stabilizer having great potential for simple and quick synthesis of silver nanocomposites has been documented for the first time in this paper. The HRTEM image of the Ag/CQDs nanocomposite depicts the crystalline nature with two distinct d-spacings of 0.22and 0.24 nm attributed to the in-plane (100) and (110) of the graphitic core or aromatic carbon and d-spacings of 0.24and 0.27 nm were also observed which is attributed to the (111) and (122) lattice planes of Ag.The size distribution histogram derived from the TEM image indicates the particles to be within 2-12 nm in diameter, complying with the Gaussian distribution. SAED patterns of the Ag/CQDs nanocomposite showed concentric diffraction rings with (111), (200), (220), and (311) lattice planes of fcc-structured silver metal, which indicates the composition of silver nanoparticles. From the XPS deconvoluted Ag3d spectrum of thenanocomposites represents the binding energies of Ag 3d5/2 and Ag 3d3/2 at 367 and 373 eV which indicates the silver to be present as metallic zerovalent [Ag (0)] oxidation state in the nanocomposite. Moreover, UV-vis spectra show a major absorption peak at 422.47 nm that contributes to surface plasmon resonance of the Ag/CQDs nanocomposite.The nanocomposite shows a zeta potential of -9.91 mV, signifying theirhigh stability. The effect of base and concentrations of the CQDs in the synthesis of Ag/CQDs nanocomposites has also been studied. The oxygen possessing functional groups present on CQDs surfacewere observed to play a significant role in reduction of Ag/CQDs nanocomposites. In addition, the nanocomposite has promising bactericidal behaviour for both gram positive and negative bacterial strains for application as an antibacterial material. The Ag/CQDs nanocomposite shows a maximum inhibition against bacterial strain Rhodococcus soli with an inhibition zone diameter of 17 mm as compared to the other strains.