Removal of organic pollutants with green and efficient methods is an important goal for researchers studying environmental pollution. Photo-Fenton systems with heterogeneous catalysts are a promising alternative for efficient water treatment. In this study, Prussian blue modified magnetite decorated multi-walled carbon nanotubes (MW-CNT) nanocomposite was prepared and for the first time applied to the photo-Fenton degradation of phenol. The catalyst was prepared by rapid hydrothermal method. XPS, SEM-EDX, XRD, FTIR methods were used for characterizing the functionalities and morphology of the catalyst. The effect of initial H2O2 concentration, catalyst mass, and initial pH of the phenol solution was investigated. Experimental results showed that 100 mg dm-3 of phenol could be degraded completely in 15 minutes at pH 7. This study describes the synthesis of the new Photo-Fenton catalyst for highly effective phenol treatment.