TiC reinforced Fe based composite powder was electrochemically prepared directly from titanium-rich slag and carbon in molten CaCl₂–NaCl at 800 °C. The reaction pathway from the slag and carbon to TiC–Fe based composite powder was investigated by examination of partially and fully reduced samples using XRD and SEM with EDS analyses. The process of reduction and the carbiding process can be divided into the two main stages. The first stage of the process is electrochemical reduction, while the second stage is a synergetic reaction of electrochemical de-oxidation and carbiding. During the second stage, TiC forms from TiC_xO_1−x, in which the carbon atoms substitute for oxygen atoms successively to give stoichiometric TiC. The TiC grains initiate the heterogeneous nucleation of the TiC–Fe based alloy particles with a multi-core microstructure.