Neutron induced prompt gamma-ray spectroscopy(NIPS) system measures the prompt gamma-ray emitting by the interaction of a neutron with various materials. This system will be of great benefit to scientists worldwide, since it provides the non-destructive measurement of many element in either solid or liquid wastes. In this study, the full-energy-peak (FEP) efficiency calibration for a HPGe detector was constructed in the ${gamma}$-ray energy range from 80 keV to 8 MeV, using $^{l33}$Ba and >TEX>$^{152}Eu$</TEX> RI sources and $ ^{35}Cl(n, ${gamma}$)^{36}Cl$</TEX> thermal neutron captured reaction. The FEP efficiency curve for the higher energies using the $^{35}Cl(n, ${gamma}$)^{36}Cl$</TEX> reaction was normalized with the curve obtained from the RI sources, since the accurate activity of its prompt ${gamma}$-ray is unknown. The average thermal neutron flux was theoretically calculated using the FEP efficiency curve for the KCl standard solutions. The NIPS system equipped with a ${gamma}$-${gamma}$ coincidence setup with two n-type coaxial HPGe detectors was considered in order to reduce the interfering ${gamma}$-ray background. The FEP efficiency curve for the ${gamma}$-${gamma}$ coincidence system was also obtained for full energy range. The performance of the normal and coincidence NIPS system was tested by comparing signal-to-noise ratio in each mode using the reference sample.e.