A copper-, ligand- and amine-free Sonogashira coupling reaction catalyzed by commercially available palladium on carbon (Pd/C) with low loading (0.4 mol% Pd) has been developed. Under optimized reaction conditions, aryl iodides bearing electron-withdrawing and –donating groups were coupled with aromatic terminal alkynes as well as aliphatic terminal alkynes to give the corresponding internal alkynes in good to excellent yields. Furthermore, the reaction efficiently proceeded using wet type Pd/C and/or under aerobic conditions. Our catalytic system is easy to handle and environmentally-friendly due to non use of copper salts, ligand and amine as a base.