Highly effective and stable palladium nanoparticles (Pd NPs) supported on graphene oxide (GO) were synthesized, characterized and applied for dehydrogenation of dimethylamine-borane (DMAB). Monodisperse Pd NPs were synthesized with the ultrasonic reduction method in the presence of oleylamine and GO as support matrices at room temperature. Almost uniformly distributed Pd (0) nanoparticles in size of 3.89 nm were isolated in a reproducible manner by filtering through the reaction mixture. They were characterized by TEM, HRTEM, XRD, Raman, and XPS. It was found that Pd@GO NPs are stable and one of the most active catalysts in the dehydrogenation of DMAB. This catalyst with its turnover frequency of 38.02 h(-1) exhibits one of the good results among all the catalysts prepared in the literature for dehydrogeneration of DMAB. Significant activation parameters of the catalytic dehydrogenation reaction were also calculated, and the activation enthalpy (Delta H-#), activation entropy (Delta S-#) and the apparent activation energy (Ea) were found 16.5 kJ mol(-1), -179 J mol(-1) K-1, and 18.6 kJ mol(-1), respectively. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.