Sunki Mandarin [Citrus sunki (Hayata) hort. ex Tanaka] is a type of micromandarin from South China largely used as a rootstock in Brazil. Cleopatra mandarin (Citrus reshni hort. ex. Tanaka) is a well-formed tree, ornamental, with red-orange fruits. The main objective of this work was to analyze the chemical composition of the essential oil in leaves of accessions of Sunki and Cleopatra mandarins and hybrids. The essential oils were obtained from the leaves by hydrodistillation in a Clevenger-type apparatus and analyzed by gas chromatography/flame ionization detector (GC/FID) and GC/mass spectrometry (GC/MS). The oil yields ranged from 1.27% (BCG562 â Hybrid of âSunkiâ C12080) to 0.33% (BCG564 â Sunki from Florida) (dry weight basis), and fifty-five constituents were detected. The major constituents were Î²-pinene (2.5â49.9%), limonene (0â49.0%), sabinene (0.5â35.2%), linalool (0.7â27.3%), thymol methyl ether (0â22.3%), p-cymene (0.2â21.2%), Î³-terpinene (0â15.1%), 1.8-cineole (0â11.0%), terpinen-4-ol (0.5â9.4%), (E)-Î²-ocimene (0.6â6.4%), Î±-pinene (1.1â4.4%), (E)-nerolidol (1.0â3.2%), Î±-terpineol (0.4â3.0%) and myrcene (0.7â2.4%).