The Electro-Fenton process can generate reactive oxygen species capable of oxidizing refractory organiccontaminants. However, low regeneration efficiency of Fe2+ restricts its application. Herein, hydroxylamine(HA) was added into the Electro-Fenton (HA/Electro-Fenton) process to accelerate the transformationof Fe3+ to Fe2+. Using dimethyl phthalate (DMP) as target contaminant, the HA/Electro-Fenton systemalleviated the two-stage reaction process and accelerated the removal of DMP in the pH range of 2.0–6.0. With improving DMP concentration from 5 mg L-1 to 50 mg L-1, their degradation rate increased in theHA/Electro-Fenton system, while decreased in the Electro-Fenton system. The addition of HA had negligibleeffect on electro-generation of H2O2, but facilitate the redox cycle of Fe3+/Fe2+ and the generation ofhydroxyl radicals, thus improving the degradation of DMP. The final transformation products of HA wereN2, N2O, and NO3. The presence of PO4 3 improved DMP degradation, while Cl and organic matters inhibitedDMP removal in varying degrees. This study provided useful reference to solve the low efficiency ofFe3+/Fe2+ cycle and expand the pH application range in the Electro-Fenton process.