CoWO<inf>4</inf>/PbWO<inf>4</inf> ceramic nanocomposites with an interface formation were prepared using a simple co-precipitation method and were characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), zeta potential measurement, energy dispersive X-ray spectroscopy (EDS) and high-resolution transmission electron microscope (HRTEM). DC conductivity (σ<inf>dc</inf>) has been studied for variable temperature. The thermoelectric study was done, and related parameter such as Seebeck coefficient (S) and power factor (P) was calculated and discussed in detail. Enhanced σ<inf>dc</inf> and S were observed for CoWO<inf>4</inf>/PbWO<inf>4</inf> nanocomposites due to creation of space charge layer (SCL) at the interface. Interface formation between the CoWO<inf>4</inf> and PbWO<inf>4</inf> nanoparticles creates SCL which leads to increase the σ<inf>dc</inf> and also interface acts as a barrier to scatter the charge carriers, thus enhancing the S. © 2021 Elsevier B.V., All rights reserved.