The variation of sugar, acid and vitamin C contents in fruits of red flesh kiwifruit （Actinidia chinensis） ＂Hongyang＂ and green fresh kiwifruit （A. deliciosa） ＇Jinkui＇ were investigated during fruit development. The results showed that the to- tal sugar soluble contents of ＂Hongyang＇ and ＇Jinkui＂ during fruit development ex- isted different variations. With the upward trend of ＇Hongyang＇ fruit development, 95 days after full bloom （DAFB）, the total soluble sugar accumulation was relatively slow, and then rose rapidly until harvest with the maximum content （6.87%）. While ＇Jinkui＇ fruit showed a fluctuant process, rising in 50 DAFB, then declining, then rising rapidly and decreasing slightly right before harvest. The variation of fruit titrat- able acid between them was more consistent, which was increased and then de- creased. The only difference was that the titratable acid content of ＇Jinkui＇ fruit de- creased slowly from the late of fruit development to fruit ripening, similar to the maximum value, but that of ＇Hongyang＇ fruit decreased rapidly in the late. Titrat- able acid contents of them in the maturity were 1.08% and 1.20%, respectively. The trends of sugar acid ratio for ＇Hongyang＇ and ＇Jinkui＇ fruit were quite different. ＇Hongyang＇ fruit increased slowly and then rapidly; ＇Jinkui＇ changed from decreas- ing to increasing, followed by slight decreasing in mature stage. In addition, the two kiwifruit varieties had a similar change trend of Vc content during fruit development, which changed from rapid increasing to declining, followed by slight growing in the harvest. The changing tendency of ＇Jinkui＇ fruit was later than that of ＇Hengyang＇.
