Similar to Cu(Fe) or Au(V), the Al(Mn) system exhibits at low temperatures aT2negative dependence of its impurity resistivity. We present NMR data, taken on both27Al and55Mn. At helium temperatures, the55Mn resonance has a big negative Knight shiftK= −2.05%. Its spin‐lattice relaxation rate is frequency independent, and verifies a Korringa relationship. In high field, the27Al line is split into a main line and two satellites. The first one with &Dgr;K1/&Dgr;KAl= −1.09 is attributed to first nearest neighbors of Mn. The temperature dependence of the Knight shift of the first Al nearest neighbors is much bigger than expected, and can be described by a (T+&thgr;)−1law, with &thgr; = 2000±300°K. The fact that low‐temperature local susceptibilities are in good agreement with Hartree‐Fock theory and that the relaxation rate is frequency independent indicate that the localized spin‐fluctuation theory is appropriate to describe that system.