This paper introduces the new technology of exploring fast neutron for recent year. They are the rejected Y-ray, thermal neutron, coincidence spectrometer of the particles with electricity,'He central spectrometer of high resolution and wide energy range (0.1 ~ 15. 0 MeV)with proportion counter, fibrous brighten body with hydrogen used for rejecting Y-ray, neutron position distribution and the measurement of neutron energy spectrum, the fibrous brighten glass body with lithium used for long neutron counter for measuring average neutron energy,the direct exploration of neutron, the exploration and polarization of multielement matrix fast neutron used for the nuclear physics of the middle and high energy and heavy ion,the exploration used for verifying the image of neutron resource,the energy of entrance Lie nuclear and accompany particle technology of the neutron with high energy and so on. They are important for the development of the neutron metrology.