This paper presents a summary of degrading organic compounds of nuclear laundry water by ozonation in different conditions of pH, hydrogen peroxide and ultraviolet radiation. The degradation of organic compounds was analysed by chemical oxygen demand (COD), total organic carbon (TOC) and biochemical oxygen demand (BOD). The optimal degradation conditions were at pH 7 with ozone, UV radiation and hydrogen peroxide addition. The transfer of ozone increased significantly, thus resulting in decreased treatment time compared to ozone treatment alone. The reductions of COD, TOC and BOD were 46%, 32% and 70%, respectively.