The pseudobinary solid solutions of Y
2+x(Co
1-yFe
y)
17-2xintermetallic compounds with the hexagonal Th
2Ni
17type structure have been investigated in relation to their magnetocrystalline anisotropy. It was found from X-ray diffraction measurements on magnetically oriented powder samples that the sign of the anisotropy constant of the compounds changes at certain values of

and

. It is noted that in the compounds with small Fe content (

) their stoichiometric character (

) plays an important role in determining the sign of the anisotropy constant.