A one step, additive free protocol for ultrasound assisted synthesis of cuprous oxide (Cu2O) nanoparticles using glycerol as a green and sustainable solvent has been developed. The glycerol plays multiple roles in nanoparticle synthesis such as solvent, promoter, reducing agent and capping agent. It assists to control the crystal morphology of obtained Cu2O nanoparticles. The Cu2O nanoparticles were characterized with the help of XRD, TEM, HRTEM, EDS, FT-IR, XPS, BET surface area and TGA techniques. This is simple, green, inexpensive and capping agent free method for the synthesis of Cu2O nanoparticles. Furthermore, we showed catalytic applications of prepared Cu2O nanoparticles in catalysis for the coupling reaction between aryl halide and aromatic amine. (C) 2015 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.