The effects of nanosize copper oxide and basic copper carbonate on the physical and mechanical properties of flakeboards were investigated according to ASTM Standard D-1037, and the curing process of phenol formaldehyde (PF) resin containing copper compounds was further investigated using dynamic differential scanning calorimetry (DSC). The results showed that nanosize copper oxide had no or slightly beneficial effects on the mechanical properties and dimensional stability of the flakeboards. While basic copper carbonate increased thickness swelling and water absorption to some extent, the difference was not statistically significant. The DSC results indicated that the comparable activation energy and reaction enthalpy, obtained from nanosize copper oxide treated samples, contributed to the higher degree of conversion of PF resin and undiminished bonding strength of flakeboards, which is probably related to the acceleration of the addition reactions taking place among small molecules in PF resin and the enhancement of heat transfer of composite mat caused by nanosize copper oxide.