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The results of a comprehensive microstructural study of ternary and quaternary phases in air cast Al85Ni11-xFexLa4 (where x = 2 and 4 at.%) polycrystalline alloys by means of optical microscopy, scanning electron microscopy, transmission electron microscopy, scanning transmission electron microscopy, energy dispersive X-ray microanalysis, and X-ray diffraction are presented. It was found that these alloys contain several phases, namely fcc-Al, Al11La3, Al3Ni1-xFeх, Al9Ni2-xFex, Al8Fe2-xNixLa and Al3.2Fe1-xNix in the form of δ-layers in the Al8Fe2-xNixLa particles. High density of other defects in the quaternary Al8Fe2-xNixLa particles were found and their formation could be caused by dendritic type of growth of this phase. The crystal structure of all these defects was revealed by high resolution scanning transmission electron microscopy together with atomic resolution energy dispersive X-ray microanalysis. The thermal stability of the ternary and quaternary phases were also studied. The Al8Fe2-xNixLa phase is metastable and undergoes an irrevesable transformation: Al8Fe2-xNixLa→Al9Ni2-xFex +Al11La3.On the basis of all these data, a sequence of solid phase reactions in these alloys during cooling and heating is proposed.