Abstract: In the present work ZnO nanoparticles are prepared by sol gel process and doped with 6 % Aluminium . Inherently conducting PPY-ZnO (Al doped ) nanocomposites were synthesized with varying amount of Al – doped ZnO via in-situ polymerization. These composites were characterized by FT-IR, XRD, TGA, and DSC. The FT-IR results show broadening and shifts of peaks towards lower wave number in all composite samples suggesting better conjugation and some chemical interaction between polypyrrole and zinc oxide nanoparticles. DSC and TGA data suggest that PPY- ZnO( Al-doped ) nano composites have high thermal stability due to better conformation and compactness and reduction of grain boundary volume with the loading of Al-doped zinc oxide nanoparticles, that increase the conductivity of composites.. The X-RD analysis demonstrated the amorphous nature of polypyrrole and its composites with Al- doped nanoparticles of ZnO as well no indication of crystalline peaks.