Iridium is one of the most important coating materials in high-temperature oxidation protective field, due to its excellent physical and chemical properties. On the basis of comparison and analysis of various preparation methods of iridium coatings, the preparation of iridium and iridium alloy coatings by electrodeposition in molten salt is reviewed in the present paper. The apparatus and pretreatment procedure of electrodeposition are introduced. The effects of processing parameters of electrodeposition on preparation of the coatings are discussed. The summary of properties and applications of iridium and iridium alloy coatings is presented. Several key issues which need to be studied hereafter are put forward.