ESR of Fe^(3+) and NMR of 7Li and 93Nb in LiNbO3 single crystals, doped with 0.010. 0.077, and 0.385 wt.% of Fe, have been investigated by employing Varian spectrometers. Though the signal intensities are proportional to the Fe concentration, the parameters are found to be insensitive with impurity levels. From NMR data of 7Li and 93Nb which were measured a; 15 MHz, the quadrupole parameters are determined, and found to be also insensitive to the impurity concentration, compared to those found in the pure crystal. The central linewidth and T1 of 7Li, however, turn out to be dependent on the impurity level and are discussed.