Abstract: The floral colors of commercial Phalaenopsis type dendrobium cultivars with different colors were measured by a spectrophotometer，the flavonoid composition in the flowers were analyzed using a high performance liquid chromatography combined with mass spectrometry，then，the relationship between the floral color parameters and the flavonoid contents were discussed. The results showed that the floral colors of commercial Phalaenopsis type dendrobium cultivars mainly distributed in purple and pink region，and the color of labellum was darker than that of petal and sepal. Linear relationships between floral color parameters and flavonoid contents were discovered. The anthocyanins were the major factors affected the floral colors of Phalaenopsis type dendrobium cultivars：The total anthocyanin contents negatively correlated with lightness L^*，chromatic component b^* and hue angle h，however，positively correlated with chromatic component a^*. Furthermore，there were 28 anthocyanins（all were acylated cyanidin-3,7,3′-triglucoside）and 19 flavonol glycosides（the aglycones were quercetin，kaempferol，and isorhamnetin）were tentatively identified，based on that，the metabolic pathway of flavonoids in Phalaenopsis type dendrobium flowers were speculated. The study also provided suggestion for the floral color breeding of Phalaenopsis type dendrobium cultivars.

Key words: Phalaenopsis type dendrobium, floral color, flavonoid