Abstract: In order to determine the aroma characteristics of the essential oil of Pelargonium graveolens L'He'rit. chromosome doubling seedlings, and to provide theoretical direction for developing new variety of Pelargonium graveolens. The chemical constituents of the Geranium oil from cutting, tissue cultured, polyploidy seedlings were analysed by GC-9A, and compared to the major components of Pelargonium rosum oil and Bour Geranium oil. There was the same kind of chemical constituents, but their content varied among all the tested oils. The content of geraniol, geranyl formate and linalool was significantly higher, but there were fewer citronellol, citronellyl formate and rose oxide in oils of tissue cultured and polyploidy seedling. The content of citronellol was 26.1% , and geraniol was 14.81% , andβ-gurjunene was 4.77% in the oil of polyploidy seedlings. Chromosome doubling of Pelargonium graveolens plants is a good way to improve its essential oil quality, and the content of citronellol and geraniol is similar to Bour Geranium oil.