This study investigated the volatile flavor composition of essential oils from Chrysanthemum zawadskii var. latilobum Kitamura and Aster yomena Makino. The essential oils obtained by the hydrodistillation extraction method from the aerial parts of the plants were analyzed by gas chromatography (GC) and GC-mass spectrometry (GC-MS). One hundred (95.04%) volatile flavor compounds were identified in the essential oil from the C. zawadskii var. latilobum Kitamura. The major compounds were valencene (10.82%), δ-cadinol (9.77%), hexadecanoic acid (8.70%), 2-methyl-4-(2,6,6-trimethylcyclohex-1-enyl) but-2-en-1-ol (3.67%), and 2-(2,4-hexadiynylidene)-1,6-dioxaspiro[4,4]non-3-ene (3.57%). Ninety-eight (93.83%) volatile flavor compounds were identified in the essential oil from the Aster yomena Makino. The major compounds were and 3-eicosyne (13.61%), 9,10,12-octadecatrienoic acid (7.8%), α-caryophyllene alcohol (6.83%), 9-octadecynoic acid (6.03%), and α-caryophyllene (5.74%). Although the two plants are apparently very similar, the chemical composition of the essential oils was significantly different in quality and quantity. In the case of C. zawadskii var. latilobum Kitamura, the sesquiterpene, valencene was found to be 10.82%, but it was not identified in A. yomena Makino. δ-Cadinol appeared higher in C. zawadskii var. latilobum Kitamura than in A. yomena Makino. A clear characteristic of A. yomena Makino essential oil is that it has a high content of caryophyllene derivatives. The α-caryophyllene alcohol contained in A. yomena Makino was relatively high at 6.83%, although the compound was not identified in C. zawadskii var. latilobum Kitamura. Also α-caryophyllene was shown to be higher in A. yomena Makino than in C. zawadskii var. latilobum Kitamura.