Abstract Thermoelectric (TE) is able to transform heat into useful energy, and early investigations on TE materials have mainly been focused on inorganic materials, but the high processing cost and low manufacturability restrict the wide applications. Polymers-based materials are promising alternatives for TE uses due to their relatively low cost, good processability and reasonable malleability. This chapter is to provide a comprehensive summary of a variety of conducting polymers-based TE materials including poly(acetylene), PEDOT, poly(thiophene), poly(aniline), poly(pyrrole), and poly(carbazole). Conducting polymer-inorganic TE composites and carbon-based nanostructures/polymer TE nanocomposites are also summarized.