Ni-TaC composite powder has been synthesized electrochemically from the mixture of NiO, Ta2O5 and carbon in molten CaCl2-NaCl at 800 degrees C. The reaction pathway was investigated by examination of the partially and completely reduced samples recovered from reduction of the NiO/Ta2O5/C pellets in combination with direct extraction of TaC. The results showed that the composite powder with the multicore-shell structure involving the nano-sized TaC particles located inside the micron-sized Ni matrix was formed through the electrochemical route. Ni metal acted as a catalyst to accelerate the reduction of the cathodic pellets by generation and recovery from Ni-Ta alloys. The electrochemical route in molten salt achieved the preparation of TaC and metal-based TaC composites at a relatively lower temperature. (C) 2015 The Electrochemical Society. All rights reserved.