In this work, the sulfonic acid (-SO3H) group terminated Fe3O4@SiO2 magnetic spheres were prepared. Polypyrrole (PPy) was in-situ polymerized on Fe3O4@SiO2 -SO3H spheres due to the dual roles of the -SO3H groups: acting as both "anchoring sites" for adsorbing of pyrrole monomer and dopant agent in PPy. By adsorbing gold nanoseeds on the as-prepared Fe3O4@SiO2-SO3H@PPy spheres followed the seed mediated growth method, the multifunctional Fe3O4@SiO2-SO3H@PPy@Au spheres were obtained. The application of Fe3O4@SiO2-SO3H@PPy@Au spheres in surface-enhanced Raman scattering (SERS) was investigated, and the results exhibited the enhancement in the order of 10(4) using 4-aminothiophenol as the probe molecule. (C) 2016 Elsevier B.V. All rights reserved.