The textile industry consumes considerable amount of water during dyeing and finishing operations. Hence, wastewater discharged in rivers or public sewage treatment plants are highly contaminated. Their treatment had been necessary for human welfare and sustainable environment. Present study deals with the detailed investigation of photocatalytic degradation of aniline yellow carried out in the presence of an aqueous suspension of ZnO irradiated with visible light in a batch reactor. It was observed that photocatalytic degradation of aniline yellow obey pseudo-first order kinetics according to Langmuir-Hinshelwood model. The influences of various factors viz irradiation time, initial dye concentration, Na2CO3, NaCl and K2S2O8 on degradation efficiency were systematically studied. The decolorization and extent of degradation of dye was determined by UV-Vis spectrophotometer and COD reflux method, respectively.