Treating wastewater using transition metal oxide nanocomposites as efficient photocatalysts has received more attention in recent years. In this work, to develop a new efficient photocatalyst based on metal oxides, the α-Fe2O3/Mn2O3 heterojunction nanocomposite was prepared via a facile one-pot hydrothermal precipitate technique and characterized by FT-IR, XRD, UV-Vis, PL, SEM and TEM techniques. The results confirm the successful formation of α-Fe2O3/Mn2O3 nanocomposite. The as-prepared α-Fe2O3/Mn2O3 was assessed for the photodegradation of methylene blue (MB) as a model wastewater under visible light irradiation. The photocatalytic activity for degradation of MB was calculated to be 96.7% within 90 min. The kinetics of experimental data were studied using the Langmuir mechanism, resulting in a rate constant of 0.02521 min-1. The effect of different scavengers on photodegradation efficiency was investigated and the results predicted that the O2-° radicals are responsible for the degradation of MB dye molecules. The reusability after six cycles was studied without significant activity change, confirming the photocatalytic efficiency and stability of α-Fe2O3/Mn2O3 nanocomposite. Therefore, the as-prepared α-Fe2O3/Mn2O3 is a promising photocatalyst in the photodegradation of other organic dyes.