Hybrid polymer-metal nanospheres are potential nano-sized medical devices that can provide multi-functions such as medical imaging and drug/biomolecule delivery. Gold nanoparticle-based hybrid nanospheres are particularly attractive owing to the unique optical and electronic properties that they possess. The polymer in hybrid nanospheres can be tasked for cancer cell targeting, DNA delivering etc. In the current investigation, a simple one-pot synthesis method was developed for producing folic acid-chitosan-capped gold ([email protected]) nanospheres. These nanospheres consisted of a flower-like gold nanoparticle core and a cross-linked folic acid (FA)-conjugated chitosan shell. During the synthesis of [email protected] nanospheres, FA-conjugated chitosan molecules acted as a reductant for gold and also as a structure-directing agent for the formation of highly branched gold nanoparticles. The evolution of [email protected] nanospheres during their manufacture was studied using various analytical techniques and the mechanism of formation and growth was proposed. The [email protected] nanospheres exhibited high-surface-enhanced Raman scattering which could be utilised for imaging at the single molecule level. The biopolymer shell was functionalised with –NH₂ and –COOH groups, which could be readily conjugated with macromolecules, peptides, nucleotides etc. for potentially wide applications of [email protected] nanospheres in the medical field.