This study modified urea-formaldehyde (UF) resin with a modifier, and focused on properties of particleboard manufactured with the modified UF resin. The orthogonal design was used to analyze the effects of different levels of hot-pressing temperature, hot-pressing time, glue content, and waterproof agent content on the modulus of rupture (MOR), internal bonding strength (IB), and formaldehyde emission (FE) of the particleboard, and thus determined the optimum technical parameters of hot-pressing. The conclusions were as follows: (1) the modifier used in this study could significantly reduce the free formaldehyde content of UF resin and the formaldehyde emission of particleboard; (2) the optimum hot-pressing technical parameters of particleboard manufactured with the modified UF resin were hot-pressing temperature 180°C, hot-pressing time 50s/mm, glue content 12%, and waterproof agent content 0.6%. The MOR and IB under the optimum technical parameters could reach 20.7 and 0.47 MPa, and the FE was 0.85 mg/L.