The mechanical property of Ni-33Al-28Cr-5.0Mo-0.5Hf super-alloy, treated under 900 ℃ with a 10 T strong magnetic field was studied under room temperature. It was found that the bending strength of the alloy was increased by 75 % after the magnetic field treatment. But the elastic modulus was almost unchanged. Observation of the fracture section showed that the alloy gave rise to some ductile fracture characteristics after treated by the magnetic field. But it exhibited a pure brittle fracture without the magnetic treatment. Microstructure observation showed that piece and fine particle Heusler phases （Ni2AlHf） separated from NiAl-Cr（Mo） phase boundary were partially dissolved after treatment of the strong magnetic field.