A one-pot hydrothermal method was used to prepare reduced graphene oxide mediated CuS/MnS (CMS/rGO) nanocomposites. The XRD result revealed that the hexagonal structure of CMS/rGO with the crystallite size is about 24 to 35 nm, respectively. The presence of rGO in the CMS structure was confirmed through Raman analysis. The chemical states of CMS3/rGO nanocomposites were confirmed by the XPS analysis. From this, the observed binding energy values are in good agreement with the presence of Cu, Mn, S, O and C, respectively. The rod-like morphology of the CMS3/rGO nanocomposites was obtained by using HR-TEM. The optical property of the product was analyzed through UV-DRS and PL. The observed absorption and emission peaks are red-shifted when CuS/MnS concentration increases. It is attributed due to the increases in crystallite size. The calculated band gap energy values are decreased with increasing crystallite size. The electrochemical properties of the products show a pseudocapacitor nature (832 Fg−1) with excellent capacitance retention of 97%. The degradation efficiency of CMS3/rGOcatalyst nanocomposite shows a good efficiency of 96% and 91% against CR and CV dyes.