Magnetic after-effect and induced uniaxial anisotropy investigations have been carried out on lithium ferrite polycrystalline samples of initial compositions Li
0.5+xFe
2.5-xO
4(

). A directional order phenomenon has been observed, which is attributed to the migration of interstitial lithium. This phenomenon is characterized by an after-effect band at about 240°K and the creation of an uniaxial anisotropy of about 90 erg/cm
3, which corresponds to 2.5×10
19interstitial lithium per cubic centimeter.