Cotton mealybug, Phenacoccus solenopsis (Tinsley)has a new distribution and attack important host plants such as cotton (Gossypium barbadense L), okra (Abelmoschus esculentus L.) eggplants(Solanum melongena L.) ornamental plants and certain weeds growing in Giza and Qalyubia Governorates. This studies carried out in Egypt, during two seasons (March to December, 2014 and 2015).The predators ladybird beetle "Ccoccinella septumpuctata L., Scymnus syriacus Mars, Hyperaspis vinciguerrae Capra, Orius laevigatus (Fieber), true spider Cheiracanthium isiacum Cambridge (Clubionidae : Arachnida) . and Chrysoperla carnea (Stephens) were recorded in association with P .solenopsis in previous Governorates. The feeding potential of the predator, C. carnea larvae were studied under semi-field conditions on cotton plants grown under green house during summer seasons in environment-controlled chambers. The population of cotton mealybug was recorded before and after release of the predator C. carnea. The mean results of the reduction percentage after 1, 3, 5 and 7 days from the release of different rates of predator larvae (5, 10 and 20 larvae) were 90.5 %, 86.8 %, and 86.05 % for adults, and 96.03 %, 92.4 %, and 94.6 % for nymphs of P. solenopsis. The results indicate that five larvae C. carnea per 100 nymphs of the pest can be used as a biological control against P.solenopsis during the management programme