The staggered local field at boron nuclei in the anti-ferromagnetic phase o
f NdB6 has been measured by B-11-NMR. The angular dependence of the local f
ield is explained as a type I antiferromagnetic structure by taking the dom
ain distribution into account, which is consistent with that obtained by th
e neutron scattering measurement. The origin of the local held is explained
as mainly the dipolar field from the magnetic moment at the Nd site. The s
aturated magnetic moment is estimated to be 1.6 mu(B)/Nd.