Recent progress of x-ray magnetic circular dichroism (XMCD) studies for Heusler alloy compounds which are expected as high spin-polarized materials is summarized. For some Heusler alloys forming X2YZ compositions, where X and Y are transition-metal (TM) elements and Z is non-TM element, the element-specific magnetic properties by XMCD are investigated to understand the electronic structures. At first, a principle of XMCD spectroscopy is introduced. Second, the research interests in Heusler alloys are explained. Then, the results of XMCD for equatorial XX’YZ composited Heusler-type spin-gapless semiconductor CoMnFeSi and CoFeCrAl are discussed considering the atomic ordering. Further, the case both X and Y are Mn and Z is Ga, Mn3Ga, is also discussed with the interfacial thermal diffusion probed by XMCD.