Abstract:In order to understand the volatiles in flowers of Dendrobium, the constituents and relative contents in flowers of D. chrysotoxum Lindl., D. lohohense T. Tang & F. T. Wang, D. hancockii Rolfe, and D. densiflorum Lindl. were determined by solid phase microextraction (SPME) and gas chromatography coupled with mass spectrometry (GC-MS). The results showed that there were 57 volatile compounds identified in four species, including esters, terpenes, alcohols, alkanes, aldehydes, ketones, quinines, aromatics, nitrogenous compounds. The composition and contents of volatiles in flowers were significantly different among four Dendrobium species. The main aromatic constituents were 3-carene in D. chrysotoxum with relative content of 84.606% and D. hancockii (71.251%); methyl salicylate (57.449%) and D-limonene (22.416%) in D. lohohense; 2-methylene-4,8,8-trimethyl- 4-vinyl-bicyclo[5.2.0]nonane (82.013%) and α-farnesene (4.699%) in D. densiflorum. Thus, these would provide references for aromatic cultivar breeding and essential oil product development of Dendrobium.