We show that multiphoton thiol–ene polymerized structures comprise unreacted thiol moieties, which can be used for postpolymerization gold metallization. Some of the thiol groups located at the surface are not involved in thiol–ene reactions and, therefore, can serve as nucleation seeds for the synthesis of ∼50 nm sized gold nanoislands. Additionally, we show that the nanoislands can be used for immobilization of fluorescent molecules. We observed a significant enhancement of the fluorescence signal on the nanoisland-functionalized polymer structures when compared to the structured polymers without gold. To show a possible application, we bound peroxidase to the gold nanoislands. Peroxidase activity has been verified by chemiluminescence of the converted luminol substrate.