The Zr–Cr–Si ternary system has been investigated over the whole composition by powder X-ray diffraction (PXRD) and scanning electron microscope equipped with energy dispersion spectroscopy (SEM-EDS). The ternary compound Zr4Cr4Si7 has been confirmed to exist in this system and its crystal structure data was acquired by Rietveld method. Rietveld refinement confirms that this ternary phase belongs to the Zr4Fe4Si7-type structure with space group I4/mmm (no.139) and lattice parameter a = 1.3199(6) nm and c = 0.5182(5) nm. The existence of ternary compounds i.e. ZrCrSi2, Zr2Cr4Si5, ZrCrSi and Zr2Cr3Si has also been confirmed at 973 K. The solid solubility of Cr in Zr–Si binary compounds and that of Si in α-ZrCr2 and Cr are determined to be between 1.5 at. % and 6.8 at. %. No remarkable solubility is determined in the other compounds. The results show that there are 19 single-phase regions, 40 two-phase regions and 22 three-phase regions in the studied isothermal section.