57Fe Mössbauer spectroscopic studies of Co2Mn1 − xFexAl based Heusler compounds are presented. The cubic structure type was found for all samples of the series in XRD studies. However, a mixture of the cubic B2 and L21 structure types are not unambiguously distinguished by XRD. The present study gives evidence for a mixture of the L21 structure with additions of a large amount of B2 like disorder. The isomer shifts and hyperfine magnetic fields on 57Fe atoms are compared with theoretical values from CPA calculations.