Core-shell nanogels are attractive stabilizers and supports for catalytically active metallic nanoparticles. Herein, we present the synthesis and the characterization of a nanostructured well-defined core-shell nanogel with the ability to stabilize palladium(0) nanoparticles in its core. This hybrid nanogel displays a remarkable stability in both solid state and in solution. This feature allowed its successful application as catalyst for the Mizoroki-Heck reaction between n-butyl acrylate and a series of bromo-and iodo-arenes. The yields spanned from good to excellent, and catalyst recycling could be achieved up to three times without significant activity loss. Three-phase tests indicated that the hybrid nanogel acts as a Pd(0) nano-reservoir. The catalysis proceeds in a quasi-homogenous fashion, with part of the catalytic activity occurring outside the nanogel explaining the observed limited recyclability.