Abstract Palladium nanoparticles supported on different shapes of nanocrystalline CuO are prepared by the treatment of Cu(NO 3) 2 and Pd(OAc) 2 in polyethylene glycol (PEG-6000). The shapes of the CuO/Pd composite are dependent on the amount of PEG used. Suzuki coupling was catalyzed efficiently by the oval-shaped material, whereas the rod shape facilitates the cyanation reaction. The CuO/Pd catalyst is recovered and reused for subsequent Suzuki reactions; however, cyanation poisons the catalyst for further use. Both these reactions are very clean and high yielding.