The martensitic microstructure of Zr-Cr-Fe alloy after β-quenching are investigated by a combination of electron channeling contrast imaging (ECC), transmission electron microscopy (TEM) and electron backscatter diffraction (EBSD) techniques. All of theoretical 12 α variants inherited from one single β phase have been obtained in the current study that revealed strict Burgers orientation relationship (BOR) with respect to β parent phase. The entire martensitic microstructure consisting of these 12 α variants in the as-quenched Zr-Cr-Fe alloy can be divided into four sub-regions or morphological groups. Each sub-region, in turn, is dominated by only one type of three-variant cluster (one crystallographic group composed of three α variants) showing the self-accommodation triangular morphologies. These three variants from individual cluster share a common pole of β parent phase and are related to each other by an angle/axis pair . The preferred formation of such three-variant cluster is ascribed to the elastic interaction between variants to achieve the largest degree of self-accommodation.