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A study of fatigue behaviour of two Fe3Al based alloys with Cr and Ceaddition was performed on single edge notched (SEN) and compact tension (CT)specimens. First attempts to measure the fatigue crack growth rate v(ΔK) were carriedout. The measurement of the fatigue crack growth rate by the optical method wasdifficult to perform, because the crack propagates in a discontinuous manner and oftenthe surface measurement is not representative for the bulk crack front advance. Inconsequence, the crack growth rate was measured also by the potential method. Owingto a very similar character in the micromorphology of fatigue and static fracturesurfaces, it is very difficult to recognize the boundary between fatigue crack and finalrupture. The fatigue fracture surface shows a varied micromorphology. Besidesstriations, known from some common alloys, another micromorphological features werefound. Fractographic analysis also proved that some fatigue damage originated aheadof the crack front. However, an unambiguous interpretation of all these features in therelation with crack growth rate is not clear and thus a further study of fatigue damagemicromechanisms in this type of material is necessary.