The magnetic alignment of a crystalline powder of N,N ' -dicyclohexyl-2,6-naphthalenedicarboxamide is reported. The powder is suspended in an epoxy precursor and aligned in the magnet (6 T). Then the precursor is solidified in the magnet to fix the crystal alignment. Wide-angle X-ray analysis of the aligned crystal and the consideration of the crystal symmetry enable the determination of the direction of three principal axes of diamagnetic susceptibility tensor of the crystal with respect to the crystallographic axes. It is found that the b axis, the [(1) over bar 04] direction, and the axis normal to these two axes correspond to the magnetic axes Of chi (3), chi (2), and chi (1), respectively. Analysis of the diamagnetic anisotropy of the molecule and the molecular packing in the crystal indicates that chi (1) < chi (3) < chi (2) (<0).