The as-prepared samples of LaMnO3/Fe3O4/NGP were successfully synthesized using co-precipitation method. The structural properties of the sample were characterized using x-ray diffraction (XRD), Fourier transform infrared (FTIR) and Raman spectroscopy. The thermal stability of the sample was measured using thermogravimetric analysis (TGA). The LaMnO3/Fe3O4/NGP composite shows the orthorhombic structure of LaMnO3 nanoparticles and the cubic spinel of Fe3O4 nanoparticles. The LaMnO3/Fe3O4/NGP was also confirmed the graphite structure of nanographene platelets. The photo and sono-catalytic efficiencies performed that the present of nanographene platelets could increase the degradation of methylene blue (MB) from wastewater. The enhancement of the photo and sono-catalytic performances of LaMnO3/Fe3O4/NGP can be attributed to the high separation between electrons and holes recombination and high efficiencies. Furthermore, the LaMnO3/Fe3O4 with 5 wt.% of NGP shows the highest photo and sono-catalytic performances to degrade MB from wastewater.