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Resistance to fracture and fatigue crack growth in Ni3Al intermetallic alloy with the alloying additions of Cr, Zr, and B was investigated. The specimens were subjected to cyclic three-point bending at R=0.1. Fatigue tests were preceded making the analyses both of the structures and the microhardness of materials. Several plots of crack length increments and crack growth rates against the range of stress intensity factor were presented. Examinations of the specimen fractures mode with the help of both a SEM and an optical microscopes revealed a cleavage-like nature of fracture that have related to the material structure.