The volatile compositions of juice and peel of clementine (Citrus reticulata x Citrus sinensis var. Commune), mandarin (Citrus reticulata Blanco var. Willow Leaf) and their hybrids were analyzed by headspace solid-phase extraction (HS-SPME) coupled with gas chromatography and either a flame ionization detector (FID) or a mass spectrometer (MS). The major compounds of the volatile fractions of clementine and mandarin were limonene and limonene/gamma-terpinene, respectively. The volatile compositions of juice and peel of the same fruit showed qualitative and quantitative differences. The data analysis established the existence of three main groups based on volatile compounds that correlated with sample genotypes (clementine and mandarin) and fruit samples (peel and juice).