The magnetic ordering in PrNi5 has been investigated in external field
s up to 72 mT and at temperatures from below the nuclear ordering temp
erature up to about 20 mK. The anisotropy of magnetization was observe
d for two monocrystalline samples with different crystallographic axes
parallel to the external field. The results show that the nuclear mag
netic moments of Pr order in the basal plane of the hexagonal crystal
structure.