Three rates of Coccinella undecimpunctata L. (Coleoptera: Coccinellidae) stages release in cucumber field for controlling Aphis gossypii Glover and Myzus persicae (Sulzer)(Hemiptera: Aphididae) was repeated 4 times at 15-day intervals. The tested rates were 12000 predator larvae/ feddan/releases,6000 predator adults/feddan/releases and combinationof 6000 larvae and 3000 adults/feddan/releases. The releases were conducted during 2007 and 2008 at a location in Qalubia Governorate. This release indicated the potential use of this predator to control the targeted aphis on cucumber. Reduction in aphids' populations and subsequent yields were significant. Highest reduction and yield gain was observed when combinationlarvae and adults were released.