The effect of Sitofex (CPPU) and its combination with Gibberel­lic acid (GA3) on yield and bunch quality of Thompson Seedless grape cultivar grown at Senhera, Kalubia Governorate was studied during both 1997 and 1998 seasons. All the experimental vines were treated with GA3 at 10 ppm when cluster reached about 8-10 mm length, 20 ppm at full bloom in addition to hand thinning at 6 mm of berry diameter. Eight treatments were applied at 1997season, six treatments were ap­plied at 1998 season using CPPU in combination with GA3 or each alone in addition to control. All the previous treatments were applied when berry diameter reached about 6 mm. Results showed that sitofex alone or in combination with GA3 delayed ripening by reducing TSS and in­creasing acidity for both seasons. The Sitofex treatments in combina­tion with GA3 or alone significantly increased the total yield, cluster weight, berry weight, size, length, width, bunch compactness and rachis weight, berry shape become global at both seasons of 1997 and 1998. Whereas the bunch Index, and berry Index decreased. Percentage of berry shattering was decreased by applying Sitofex alone or combined with GA3 at 1998 season. Obtained results proved that Sitofex (CPPU) application at 5ppm + GA3 at 40 ppm gave the best bunch and berry quality, which are required for exportation.