SiC-reinforced Ni-based nanocomposite coating on aluminum alloy was prepared by an electroless deposition process. This coating technique can be used to create coatings on a variety of substrates. The majority of the literature and research on the issue focuses on the macro- and micro-scale effects of the bath composition in addition to the parameters of the process on the Ni-SiC composite coating's microstructure. Nonetheless, it has been recognized that bath composition influences on the morphology, phase structure, microstructure, and microhardness of the Ni-matrix nanocomposite coating. As a result, the current study will compare the incorporation influences of the hard ceramic SiC nanoparticles at various concentrations (0.1, 0.2, 0.4, and 0.8) g/l on the phase structure, microstructure, and microhardness of the Ni-matrix nanocomposite coating. The X-ray diffraction technique, the scanning electron microscope (SEM), and the microhardness test were used to investigate the phase structure, nanocomposite coating morphology, and microhardness, respectively.