Abstract:The compression deformation behavior of as-annealed Mg-Nd alloy sheet along rolling direction at room temperature (RT) and cryogenic temperature (CT) of -150℃ were investigated by in-situ electron backscattering diffraction (EBSD), slip trace method and in-grain misorientation angle method. The results show that the twinning mode is not affected by the deformation temperature, in contrast, the twinning nucleation rate and slip types are dramatically affected. Compared with RT compression, local stresses are obviously increased in the sample under CT compression. As a result, the twinning nucleation rate and total length of twin boundary are increased by about 10% and 8% respectively at CT under the same compression deformation strain (4%). In the meantime, non-basal slips are promoted during CT compression deformation, with the proportion of non-basal slips increasing from 45.5% at RT to 65.9% at CT. In addition, the low temperature inhibits basal slip during compression deformation, and the proportion of basal slip decreases from 54.5% at RT to 34.1% at CT.