Chemical properties of Crataegus pentagyna subsp. pentagyna, C. orientalis subsp. orientalis, C. orientalis subsp. szovitsii, C. tanacetifolia, C. azarolus var. aronia, C. monogyna var. lasiocarpa, C. monogyna var. monogyna taxa that are naturally distributed in Western Anatolia were determined in this study. Leaf and flower samples collected from Izmit, Sakarya, Balikesir, Izmir, Kutahya, Mugla and Isparta provinces of Western Anatolia to determine volatile components in 2010-2014 period were dried at room temperature. Volatile components that were obtained by dry phase microextraction (SPME) method in Suleyman Demirel University Central Laboratories were determined in Gas chromatography-mass spectrometry (GC-MS). A total of 81 volatile components belonging to 7 hawthorn taxa were determined. Volatile oil components that were identified at highest ratios were benzaldehyde (82.54%) butyraldehyde (38.27%) and (E)2-hexenal (21.67%) components.