The BaCrO4 nanoparticles were synthesized from a 0.1 M K2CrO4 and 0.1 M BaCO3 solution with stirring for 10 h. The product was washed several times with acetone and heated to 700°C for 6 h. At that time, the color of mixture was a greenish yellow. The graphene/BaCrO4 nanocomposites were prepared with graphene and BaCrO4 nanoparticles by stirring in tetrahydrofuran and heated in an electric furnace at 700°C for 2 h. The BaCrO4 nanoparticles, graphene/BaCrO4 and heated graphene/BaCrO4 nanocomposites were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The graphene/BaCrO4 nanocomposites and heated graphene/BaCrO4 nanocomposites were evaluated as a photocatalyst and discussed about kinetics study for the degradation of organic dyes, such as methylene blue and rhodamine B under ultraviolet light irradiation at 254 nm.