A headspace solid-phase microextraction (HS-SPME) method was used to extract the essential oil of Osmanthus fragrans Lour., which was then analysed by gas chromatography–mass spectrometry (GC– MS) at four different stages of flowering. The primary chemical components of the essential oil extracted from O. fragrans were linalool and its oxide, a-ionone, b-ionone, nerol, c-decalactone, 9,12,15-octadecatrienoic acid, and hexadecanoic acid, most of which were at their highest concentrations in extracts obtained from flowers at the initial flowering stage. HS-SPME using a PDMS/DVB fibre is a simple, rapid, and solvent-free method for the extraction of volatile compounds emitted from living O. fragrans. HSSPME with GC–MS can be used to determine the aromatic maturity in O. fragrans, to decide the optimal harvest date. The initial flowering stage was the best time to harvest O. fragrans.