[en] Here, we report the development of an innovative method for the direct measurement of neutron energy spectra, using CR-39 SSNTD as a passive detector. Neutrons produced from Am-Be source is used for the measurement. 5.48 MeV α particle from the ²⁴¹Am source undergo fusion with ⁹Be to form the compound nucleus of ¹³C at an excitation energy of around 14.4 MeV. Depending on the thickness of Be the excitation energy of ¹³C may vary from 10.6 MeV to 14.4 MeV. Neutron from such resonance populate various states of ¹²C depending on the structure of states. The expected neutron spectrum from Am-Be were measured using CR-39 detector from University of Calicut. The neutron energy spectrum thus obtained analyzed using the simulated spectrum from nuclear reaction code EMPIRE 3.2, Alpha straggling and tunnelling affected to spectrum is also taken in to consideration