Multiple block copolymers bearing PDMAEMA (poly(2-(dimethylamino)ethyl methacrylate), PLMA (poly(lauryl methacrylate), and PAMA (poly(allyl methacrylate) segments are synthesized via RAFT (reversibleaddition-fragmentation chain transfer) polymerization. Manipulating the cross-linkage of PAMA in the specific domain of polymeric assemblies affords micellar nanoreactors with different topological structures. After embedded with Pd NPs (nanoparticles) in the corona layer, the core-cross-linked micelles demonstrate profound catalytic activity and structural stability in the aqueous Suzuki–Miyaura coupling of aryl bromides with aryl boronic acids.