NMR experiments of 5 1 V are reported for two samples of Fe 2 VSi: one is quenched after annealing at 1073K and the other is quenched after annealing at 1123K. Free-decay signals were observed at high temperature and the hyperfine coupling constant is determined to be -5.0+/-0.5kOe/μ B for both samples, indicating that the vanadium atoms do not carry a moment. The temperature dependence of the width of the field-swept spin-echo spectra at low temperature is consistent with the commensurate and incommensurate anti-ferromagnetic spin structures proposed from neutron experiments. The magnetism in Fe 2 VSi strongly depends on the degree of atomic order.