Multicomponent systems of alkali metal halides and chromates are used as molten electrolytes for chemical current sources, heat storage materials, etc. In this work, the ternary system RbF-RbBr-Rb2CrO4 was studied. The ternary systems \MF-MBr-M2CrO4 (\M = Li, Na, K, Rb, Cs) were analyzed by comparing the types of the liquidi of the systems in the series formed by successive replacement of the alkali metal with increasing its number in the periodic system. The RbF-RbBr-Rb2CrO4 system was investigated by differential thermal analysis. Phase equilibria in the system were explored; crystallizing phases were determined; and the characteristics of the ternary eutectic and the ternary peritectic were found to be (equiv. %) 39.5 RbF, 52.0 RbBr, 8.5 Rb2CrO4, the melting point 522 degrees C and 19.7 RbF, 55.0 RbBr, 25.3 Rb2CrO4, the melting point 554 degrees C, respectively.