Herein, we investigated the activation and stabilization of Pd nanoparticles using microparticles of chitosan-functionalized with phosphine moieties. The catalytic activity of the prepared material was assessed in a series of Heck reactions, which demonstrated the potential of our catalyst concerning yields and reaction scope. Comparative experiments confirmed the superior performance of the phosphine-modified material with respect to a similar catalyst derived from non-functionalized chitosan. Finally, the prepared catalyst also exhibited appreciable activity even after four consecutive reaction runs, with minimal loss of Pd by leaching. [GRAPHICS] .