Chemical compositions of essential oils from 17 citron cultivars were studied using GC and GC/MS. To the best of our knowledge, chemical compositions of peel and petitgrain oils from seven of them were reported for the first time. Combined analysis of peel and petitgrain essential oils led to the identification of 37 components (amounting to 98.2-99.9% of the total oil) and 42 components (97.0-99.9%), respectively. Statistical analysis was applied to identify possible relationships between citron cultivars. The levels of seven components, i.e., limonene, beta-pinene, gamma-terpinene, neral, geranial, nerol, and geraniol, indicated that the cultivars could be classified in four main chemotypes for peel and petitgrain oils. Chemotaxonomic investigations were carried out to establish relations between the morphological characteristics of citron cultivars and their corresponding oil compositions.