Heterogeneous catalyst containing gold nanoparticles (AuNPs) was prepared by direct precipitation of collagen of type I as the stabilization reagent. The composite is fibrous and the AUNPs are found to form patterns of long wires. short wires, and dispersed patterns on collagen. The catalytic reduction of 4-nitrophenol to 4-aminophenol by NaBH4 in the presence of the composite was satisfactory.