The odor-active volatiles of Kinokuni mandarin (Citrus kinokuni Hon. ex Tanaka), an original mandarin orange in Japan, were characterized by a combination of instrumental and sensory analyses and compared with those of Satsuma mandarin (Citrus unshiu Marcovitch). An aroma extract dilution analysis (AEDA) of the polar fractions of Kinokuni and Satsuma mandarin peel oils identified live odorants in common as the most odoractive volatiles: (Z)-hex-3-enal, decanal, linalool, yuzuol, and (2E)-trans-4,5-epoxydec-2-enal. In addition, seven odorants were identified solely in Kinokuni mandarin as significant contributors: octanal, dodecanal, (2E,4E)-deca-2,4-dienal, geraniol, yuzunone, (2E,7Z)-trans-4,5epoxydeca-2,7-dienal, and thy mol. The odor-active volatiles in both the non-polar components of the peel oil and an extract of the juice prepared from Kinokuni mandarin were also identified. The (S)-isomer of linalool in Kinokuni mandarin peel oil was dominant in the enantiomeric distribution (92%), whereas the (R)-isomer was dominant in Satsuma mandarin peel oil (90%).