A neutral particle energy analyzer (NPA) has been developed to investigate the energy spectra of neutral particles emitted from the HL1M tokamak plasma. The NPA consists of a pair of 45o parallel electrostatic plates, a gas stripping cell, a column of channeltrons for recording ions,and the relevant instrumentation and software. There are eight energy channels in the NPA with energy ratio of 8 between the lowest energy channel and the highest one. Calibration experiment is the key issue for the development of NPA. Calibrations of energy, energy resolution and registration efficiency have been carried out. The scattering of neutrals through the stripping gas impingement, which is severe for the particle energy we concerned, has also been measured to calibrate the registration efficiency accurately. With the NPA, the heating effects of lower hybrid wave on the plasma ions in the HL1M tokamak for different plasma parameters, especially for different plasma density, have been investigated. A neutral particle energy analyzer (NPA) has been developed to investigate the energy spectra of neutral particles emitted from the HL1M tokamak plasma. The NPA consists of a pair of 45o parallel electrostatic plates, a gas stripping cell, a column of channel experiments for the development of NPA. There are eight energy channels in the NPA with energy ratio of 8 between the lowest energy channel and the highest one. Calibrations of energy , the scattering of neutrals through the stripping gas impingement, which is severe for the particle energy we concerned, has also been measured to calibrate the registration efficiency accurately. With the NPA, the heating effects of lower hybrid wave on the plasma ions in the HL-1M tokamak for different plasma parameters, especially for different plasma density, have been in vestigated.