In order to overcome the low terahertz transmittance and laser threshold of the high resistance silicon,a new type of nanocomposite material was designed and fabricated through the spark plasma sintering (SPS) technology,which can be used as an efficient terahertz filter device for terahertz waves and isolated femtosecond lasers.The overall design principle of the device is mainly based on the Rayleigh scattering.Nanoparticles with a particle size of about 100 nm can selectively pass the terahertz wave efficiently and scatter most of the 800 nm high-energy laser.The device consists of diamond nanoparticles and high-resistance silicon particles obtained by the vacuum ball milling.The high melting point of the diamond increases the laser threshold and the porous structure can further reduce the Fresnel reflection loss and enhance the terahertz transmittance by up to 90%.