The effects of old corrugated cardboard (OCC) fiber addition on high-density fiberboard (HDF) were investigated in this study. A phenol-formaldehyde (PF) resin was synthesized in the laboratory with resin solids at 50% content as an HDF binder. The physical characteristics and molecular weight of the PF resin are described herein. The laboratory HDFs were made using the OCC fiber based on 0, 20, 40, and 60% oven-dry weight addition with the laboratory-synthesized PF resin. The HDFs were tested for physical strength and dimensional stability properties according to the procedure of ASTM D 1037-99. Evaluation of the HDFs manufactured using the PF resin showed that the internal bond and bending strength properties were decreased gradually with increasing OCC fiber content. Overall, the OCC fiber can be used at a content of 40% in the substitution of raw materials for HDF manufacture. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 115: 641-645, 2010