Local atomic structural investigations of LiAlD4, which is composed of Li+ and [AlD4]−, at 40–300K were studied by total neutron scattering combined with pair distribution function (PDF) analysis for understanding of hydrogen release from LiAlD4. The results showed that the Al–D pair distribution almost unchanged, while the Li–D pair distribution clearly started to broaden and shrink above 200–250K. The shrinking of the Li–D pair distribution might lead to the local generation of LiD, which was speculated as the precursory phenomenon for the hydrogen release from LiAlD4.