Two experiments were conducted to determine the optimum conditions for azo dye degradation. First, the efficiency of Orange II degradation by the synthesized nZVIwas investigated by evaluating the effects of pH and nZVI dosage on decolorization and TOC removal efficiency. Next, an nZVI reduction process was coupled with an H2O2 process and the effects of simultaneous and sequential treatment with nZVI and H2O2 on the Orange II degradation were investigated. The UV/Vis spectra of Orange II were monitored using an Optizen 2120 UV/Vis spectrophotometer. The decolorization efficiency of the Orange II was measured at 484 nm. The total organic carbon (TOC) was measured using a Shimadzu TOC-VCSN analyzer. All reactions were conducted in triplicate and the results shown in this paper are an average of the triplicate data.