Setoka (Tangor Norin No.8) is a superior tangor cultivar cultivated in a greenhouse on Jeju Island, and its ${eta}-cryptoxanthi$n content was determined during the ripening season (September 2005 to March 2006). The ${eta}-cryptoxanthi$n content of the peel of Setoka fruits was higher than that of the flesh. Also, the ${eta}-cryptoxanthi$n content in both peel and flesh gradually increased through the ripening season from the beginning of pigmentation, and then decreased slightly late in the ripening season. The ${eta}-cryptoxanthi$n content in the peel of Setoka fruits varied throughout the season with values of 0.02 (Sep), 0.67 (Nov.), 2.27 (Dec.), 2.88 (Jan.), 2.27 (Feb.), and 2.13 mg% (Mar.). The ${eta}-cryptoxanthi$n content in Setoka fruit flesh increased throughout the ripening season with values of 0.05 (Sep.), 0.22 (Nov.), 0.57 (Dec.), 0.80 (Jan.), and 0.91 mg% (Feb).