Thermoelectric energy harvesting is one of the keystones of modern green renewable energy generation. Unfortunately, most conventional state-of-the-art inorganic semiconductor thermoelectric generators are expensive, fragile, and not flexible. Considering these limitations, we developed a flexible printable thermoelectric generator (TEG) with both n-type and p-type organic composites of reduced graphene oxide, carbon nanotubes, poly(3,4-ethylenedixoythiphene)-polystyrene sulfate, and lead sulfide composite materials. We constructed a TEG of ten alternating n-p pairs as a prototype with an effective area of 1.4 cm(2) each, which generated 13 mV thermovoltage at operating temperature difference of 77 degrees C. It demonstrates that its fabrication is scalable, printable, and relatively simple, and the resultant structure is flexible, conformal, and reconfigurable.