Abstract: The tissue equivalent proportional counters are used as active neutron dosemeters in radiation protection. A spherical TEPC was designed and employed for monitoring accelerator-based mono-energetic neutron sources. The microdosimetric spectra of 0.36, 0.65, 0.8, 1.0 and 1.3 MeV mono-energetic neutrons were obtained. The absorbed dose, mean quality factor and dose equivalent value were evaluated from the measured spectra. The comparison between H*(10) which was calculated based on the transforming factor of fluence to ambient dose equivalent and measured dose equivalent was conducted for each mono-energetic neutron. The FLUKA simulation of TEPC was also implemented for comparison. It is found that the simulated data agree well with the experimental results and both reveal a good dose equivalent response of the spherical TEPC.