Grating devices using photosensitive organic materials play an important role in the development of optical and optoelectronic systems. High diffraction efficiency and polariza- tion dependence achieved in a holographic polymer-dispersed liquid crystal (HPDLC) grating are expected to provide novel polarization controllable optical devices, such as the holographic memory for optically reconfigurable gate arrays (ORGAs). However, the optical property is af- fected by the temperature change under environments where the HPDLC devices are applied. The temperature dependence of the diffraction efficiency in holographic memory is investigated for various LC composites materials. The anisotropic diffraction induced by the alignment of LC in periodic structure in the HPDLC memory is confirmed to be maintained at high temperature over 100°C by adjusting the combination of refractive index of LC and polymer materials.