LiH is designated as a promising moderator and shielding material because of its low density ,high melting point and large fraction of H atoms .However ,lack of the thermal neutron cross sections of LiH makes numerical calculation deviate from experi-mental data to some extent .In this paper ,the thermal kernel effect of LiH was studied , the phonon spectrum of LiH based on the first principle was calculated ,and the models of LiH thermal scattering law and matrix by GASKET and NJOY codes were construc-ted .The ACE format LiH thermal neutron cross sections for MCNP were generated . Comparison between thermal scattering cross section of ZrH2 and reference results was done ,and the secondary neutron spectra were modified by parabolic behavior of Debye model .These cross section could be used in the modeling of the nuclear propulsion particle bed reactor .%氢化锂（LiH ）以其低密度、高熔点、较高的H原子份额等良好的热物性，被用作空间核热推进反应堆的慢化剂和屏蔽材料。考虑到低能区LiH热中子数据的缺失使得数值模拟结果与实际相差很大，本文对LiH热化效应机理进行初步研究，基于第一性原理方法计算了LiH 的声子谱，采用GASKET 和NJOY程序建立LiH热散射律和散射矩阵的计算模型，制作成MCNP的ACE格式的LiH热中子截面数据库。对比文献结果和ZrH2热散射截面，分析差异的原因，采用Debye模型的抛物线效应修正了次级能量分布情况。该截面值可为下一步高温粒子球床堆物理建模提供必要的数据。
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