In this article, palladium nanoparticles supported on agarose were used as an efficient catalyst for Heck–Matsuda and Suzuki–Miyaura coupling reactions of structurally different aryldiazonium tetrafluoroborate substrates in aqueous media. Heck–Matsuda reactions proceeded at 40°C whereas Suzuki-Miyaura reactions were carried out at room temperature. Both reactions required low catalyst loading. The catalyst was also recycled for the model reaction for three runs. Copyright © 2012 John Wiley & Sons, Ltd.