The chemical resistance of the ZrN powder to molten LiCl with additions of PbCl2, KCl, Li2O, LiOH, and H2O at 650 degrees C. have been thermodynamically evaluated and experimentally verified. Using complex physical-chemical methods it has been demonstrated that ZrN exhibits a high resistance to the LiCl-PbCl2 melts. After long-term exposure of the ZrN powder in these melts the PbCl2 concentration was not changed and the ZrCl4 content did not exceed 0.002 wt% in the melt and 0.23 wt% in the sublimates. An increase in temperature or molar ratio of PbCl2/ZrN, as well as appearance of the KCl modifying component insignificantly reduces the ZrN resistance to molten LiCl-PbCl2. According to the SEM analysis, a structure of the ZrN powder becomes less dense after the exposure in LiCl-PbCl2. Almost complete oxidation of the ZrN powder was found after long-term exposure in the LiCl-PbCl2 melts with Li2O and LiOH additions, and only partial oxidation was observed in melts with H2O addition. Nevertheless, a high resistance of the ZrN powder to the LiCl-Li2O melt was determined. (C) 2019 The Electrochemical Society.