Fenton Process and E-Fenton Process belong to advanced oxidation technologies(AOTs). Oxidation system consists of H2O2 and Fe2+.In Fenton system,H2O2 can generates two kinds of active HO2· and·OH under Fe2+ catalysis,so as to expedite oxidation of organic matters and deoxidizing matters. The article introduces briefly the reactive mechanism and application of Fenton Process and E-Fenton Process,the treatment technology and research progress in hard degradation waste water by catalysis and oxidation.