Effect of girdling and its time on yield, fruit quality and storage life of Flame and Ruby seedless cultivars grown in a clay loam soil in Dakahlia Governorate was studied during two seasons (1997 and 1998). Girdling was performed at different times; before flowering, after fruit-set, 2 weeks after fruit set and at véraison. This study revealed that girdling Flame seedless before flowering increased fruit set percentage, cluster compactness factor, yield, cluster weight, berry weight & size and total anthocyanin in berries skin. While, there was no effect on berries juice, T.S.S. and acidity contents. Girdling of Ruby seedless, before flowering, increased fruit-set percentage, cluster compactness factor, yield, cluster weight, berry weight and size, T.S.S., T.S.S./acidity and total anthocyanin in berries skin, and decreased acidity in juice berries. While, there was no effect on cluster length and berries juice volume. Moreover, girdling both Flame and Ruby seedless at véraison increased T.S.S., T.S.S./acidity and total anthocyanin in berries skin, while decreased acidity in berries juice. There was no effect on fruit-set percentage, yield per vine, cluster weight, cluster length, cluster compactness factor, berry weight and size. This study also revealed that girdling both Flame and Ruby seedless cultivars after fruit set or 2 weeks later improved the yield and quality. Yield increased with about 69.7 and 63.6% for Flame and 36.0 and 29.4% for Ruby seedless cultivars over the control as a mean of the two seasons, respectively. Also girdling increased cluster weight, berry weight and size, T.S.S., T.S.S./acidity and total anthocyanin in berries skin, while decreased acidity in berries juice. Berries characters were better than other treatments used drring room storage at 25-30°C and 45% R.H., this treatment decreased cluster weight loss, shattering percentage, decay percentage and total loss after 9 days. The reduction of total loss reached about 16.7 and 17.8% in Flame seedless and about 12.8 and 11.7% in Ruby seedless less compared to the control as a mean of the two seasons, respectively.