In this study, a new method was developed for the oxidation of 5-hydroxymethylfurfural (HMF) into 2,5-furandicarboxylic acid (FDCA) over Merrifield resin supported Co(II)-meso-tetra(4-pyridyl)-porphyrin (abbreviated as Merrifield resin-Co-Py). Diffuse reflectance spectra showed that Co(II)-meso-tetra(4-pyridyl)-porphyrin was successfully bonded on the Merrifield resin. The Merrifield resin-Co-Py catalyst was used for the oxidation of HMF into FDCA, and several parameters were studied. Tert-butyl hydroperoxide was the best oxidant among other common oxidants. The reaction solvent greatly affected both HMF conversion and product selectivity. High HMF conversion of 95.6% and FDCA yield of 90.4% were obtained at 100 degrees C after 24 h. Time course of HMF conversion over Merrifield resin-Co-Py showed that 2,5-diformyl-furan was the intermediate for the conversion of HMF into FDCA. The catalyst could be reused without the significant loss of its catalytic activity. (C) 2015 Elsevier B.V. All rights reserved.