Bokij and Khodashova' derived from X-ray diffraction study and coordination considerations that InF.3H2O is pseudotetragonal with a=7.90, c=4.14 8, 2=2, space group PII2/n. each indium atom is surrounded by six ligands (F and H2O) to form nearly are gular octahedron. The adjacent octahedra have common a pices forming in finitechains along the c-axis. Since the F and O scattering factors are much the same, the identification of F atoms and H2O molecules was performed on the basis of coordination considerations. The bridges between In atoms were unambiguously identif iedas fluorine atoms (F). The fouro the rligands of each octahedron are two fluorine atoms (F) and two water molecules (H2O equatorial plane of the octahedra (fluorines under fluorines in order to retain 2=2). estimated as oxygens of H2OImolecules due to the irspecifictetrahedral surrounding by FIIand H2OIIn such a lamellar structure, the layers of H2OIand H2OIImolecules interchange with the layers of F atoms. The existence of H2O layersin the InF3.3H2structure, claimed by B. and K., is notin agreement with the factth that the crystals of this fluoride have needle-like habitus and do not exhibit excellent cleavage in the plane (110). In order toresolve this contradiction and find out the proton position sin the InF.3H2o structure, we have applied the NMR method