Terahertz-wave Parametric Oscillator(TPO) based on phonon-polariton scattering is one of the promising methods for obtaining high-energy and coherent THz-wave. A high-energy THz-wave output has been experimentally demonstrated with terahertz-wave parametric oscillator based on surface-emitted configuration. The maximum THz-wave output energy of 634 nJ/pulse is obtained at 1.63 THz. The rapid tuning is achieved by rotating the injection angle of pump beam into MgO:LN crystal using an optical beam scanner. The wide tunable range is from 0.75 THz to 2.81 THz. It is excepted that such high-energy THz-wave source can meet the demands in many applications, including biomedicine, communication and environmental monitoring.