The neutron-induced neutron-production double-differential cross-sections at 100 MeV by bombarding a Fe sample with continuous energy neutron were measured. A fission ionization chamber was set to take the incident-neutron flux. Six NE213 liquid scintillators, 12.7 cm thick and 12.7 cm in diameter, were placed at 15 , 30 , 60 , 90 , 120 and 150 to detect neutrons emitted from a sample. Incident energies of neutrons were obtained by the time of flight (TOF) method. The distance from the spallation target to an NE213 scintillator was applied as the flight length of incident neutrons. The energy spectra of emitted neutrons were derived from unfolding their deposition-energy spectra with the response functions of the detectors. The response functions were also measured with the spallation neutrons above neutron energy of 20 MeV. In the unfolding process, neutron-induced neutron-production double-differential crosssections were approximated by the moving source model. The experimental results were compared with calculations of the PHITS code using the JENDL-HE file.