Within the framework of our bioorganic studies and in an effort to identify headspace volatile organic constituents (HS-VOCs) restricted to specific honey types, we performed the chemical screening of cornflower Centaurea cyanus L. honey from Poland. The main components of specific honey volatiles belong, in general, to three principal groups of organic compounds: terpenes, norisoprenoids, and benzene derivatives [1]. Other compounds, like some alcohols, branched aldehydes, and furan/pyran derivatives, can be related to the honey processing and/or storage conditions [2]. No information is presently available on those HS-VOCs that are useful for chemical authentification of the floral origin of C. cyanus L. honey. Therefore, the aim of the present study was to identify them using headspace solid-phase microextraction (HS-SPME) and gas chromatography with mass spectrometric detection as well as with flame ionization detection (GC-MS and GC-FID). HS-SPME is a solvent-free isolation technique and has been proven effective for the isolation of honey VOCs [3–5]. This paper reports the identification, for the first time, of norisoprenoids as characteristic components of cornflower honey headspace, particularly the occurrence of the bicyclic oxoedulan skeleton. Preliminary experiments were carried out in order to compare the obtained chromatograms in terms of number of extracted compounds and peak areas, and the most suitable HS-SPME fiber was selected to be DVB/CAR/PDMS. A total of 32 organic compounds was identified from the samples and are listed in Table 1 according to the elution order on a HP-5MS column. The group of C 13 - and C 9 -norisoprenoids, a class of carotenoid-derived compounds with 3,5,5-trimethylcyclohex-2-enic structures, was the most abundant among isolated HS-VOCs of cornflower honey. The dominant C 13 compound was 3,4-dihydro-3-oxoedulan (2,3,5,6,8,8a-hexahydro-2,5,5,8a-tetramethyl-7H-1-benzopyran-7-one, also known as 2,5,5,8a-tetramethyl2,3,5,6,8,8a-hexahydro-7H-chromen-7-one; 18.60–44.97%) with mass spectrum (EI, 70 eV), m/z (I rel , %): 208 (M + , 7), 193 (100), 166 (7), 151 (15), 149 (6), 124 (30), 123 (10), 122 (8), 109 (65), 107 (32), 105 (10), 93 (10), 91 (18), 81 (11), 79 (16), 57 (10), and 55 (10) that correspond to the spectra of the same C 13 -norisoprenoid found in oak wood [6]. The compound 3,4-dihydro-3-oxoedulan and the saturated analog tetrahydro-3-oxoedulan are also components of Burley tobacco [7], and the former also occurs in passion fruit [8]. However, this is the first report on 3,4-dihydro-3-oxoedulan with high abundance in honey headspace that can be useful for characterization of C. cyanus L. honey. The formation of the oxoedulan by intramolecular acid-catalyzed conjugate addition may well take place in acidic medium (e.g., hive conditions). Such reactions have already been utilized in the synthesis of the oxoedulans [9]. Polyhydroxylated C 13 -norisoprenoids (e.g., 3-hydroxy-retro--ionol) are natural precursors of edulans [10]. The oxoedulan structure contains epoxide with the oxo group in position 3, so it is more volatile in comparison with its hydroxylated precursors, which can exhibit hydrogen donor and acceptor properties in the formation of hydrogen bonds in the honey-water solution. Therefore, 3,4-dihydro-3-oxoedulan was abundant in the headspace, while hydroxylated or polyhydroxylated C 13 -norisoprenoids were not expected to be found due to their limited headspace participation. However, several lower molecular oxygenated C 9 -norisoprenoids were found: 4-oxoisophorone (3,5,5-trimethylcyclohex-2ene-1,4-dione; 4.35–11.23%), isophorone (3,5,5-trimethyl-cyclohex-2-en-1-one; 1.12–5.48%), and 2-hydroxyisophorone (2-hydroxy-3,5,5-trimethyl-2-hydroxycyclohex-2-en-1-one; 0.00–2.30%). Previous studies showed that the types and amounts of norisoprenoids are related to the honey botanical origin and have been proposed as chemical markers of the honey floral source [1].