Series of the near stoichiometric two phase (martensite + , parent + ) Co2NiGa alloys were studied. Different thermal treatments changing the microstructure were applied. After annealing for 20 h at 9000C large precipitates were dispersed, they decorated mainly the grain boundaries. For the alloys quenched from the 11000C modulated structures were observed. Furthermore, during aging at the 3500C ' precipitation process occured in the matrix.