In the present study magnetic and magnetostrictive properties of Tb(Fe1−xTx)2(T=Mn, Ga) compounds were examined by magnetic measurement, Mo¨ssbauer, and x‐ray study. Mo¨ssbauer study shows that the easy magnetization direction of the compounds may deviate slightly from the major axis of symmetry and the average isomer shift of the compounds decreases with increasing thexvalue, which was attributed to the charge transfer from 3delectrons of Mn atoms or 4pelectrons of Ga atoms into the 3dband of Fe. It was also found from x‐ray measurement that the spontaneous magnetostriction &lgr;111decreased due to Mn or Ga substitution, which can be understood on the basis of the single‐ion model. The increase of the polycrystal magnetostriction &lgr;sdue to Mn substitution was also found and can be ascribed to the increase of &lgr;100, which may be caused by the filling ofdbands due to substitution. ©1995 American Institute of Physics.