Aromatic nitro compounds have been promising industrial applications including paper production, pigments, pharmaceuticals, dyes, wood, leather, petrochemical, pesticides, insecticides, fungicides, explosives, and preservatives. US EPA (Environmental Protection Agency) declared that 4-nitrophenol (4-NP) has been recognized as a non-biodegradable pollutant and therefore, a very important to develop an effective method to either modify or remove 4-NP before releasing it into the environment. In that concern, we have developed an efficient, heterostructure composite of NiO-FeS2 via hydrothermal. The 4 mg catalyst dose and 10 mg/L concentration of 4-NP are the optimum conditions for complete reduction of 4-NP to 4-AP by prepared NiO-FeS2 composite.