A real-time Bonner sphere spectrometer (BSS) has been developed for spectral neutron measurements with the HL-2A Tokamak. To correct and verify the accuracy of the neutron spectrum from the BSS, the BSS system was calibrated using monoenergetic neutron beams in the energy range of 100 keV–5 MeV. The response function of the BSS was corrected based on the calibration results, and the corrected BSS system was verified by unfolding monoenergetic neutron spectra. Fusion neutron spectra on the HL-2A have been obtained from the cali-brated BSS system for the first time.