The Mn+1AXn phases, crystalized in hexagonal P63/mmc, have attracted considerable interest for its metallic properties and mechanic properties. In 2013, Liu et al reported that a spin-density-wave (SDW) transition has been found in Cr2GaN at TN = 170 K. It is also noticed that the transport properties of Cr2GaN is very similar to the parent compound of iron-based superconductors, and the formation of the SDW state is also theoretically interpreted in terms of the nesting of Fermi surfaces of the two-dimensional-like electronic structure. The significantly correlated nature of the d band electrons in Cr makes the magnetic coupling and ferromagnetic/antiferromagnetic ordering are very sensitive to other elements in MAX compounds. Thus it would be very interesting to determine the magnetic structure of the nitride Cr2GaN.