Aphelinids (Hymenoptera : Aphelinidae) are  the most important  parasitoids of, armored scale, soft scale insects ( Hemiptera: Coccoidea )   and whiteflies ( Hemiptera: Alyerodoidea). The present work dealt with the diagnosis and abundance and the role of this group in controlling  armored scale, soft scale insects and whiteflies. The results indicated that  17 parasitoids and hyperparasitiods were reared from samples of armored , soft scale insects and whiteflies in different locations in Egypt. These parasitoid and hyperparasitiod species were collected from 7 armored, soft scale insects and whiteflies and  distributed  in 5 Governorates (Alexandria, Assuit, Ismailia, Fayoum  and Matruh). The maximum rate of parasitism of armored scale insects parasitoids ranged between 12-59% during the two years under consideration.  While  the maximum rate of parasitism of soft scale insects and whiteflies parasitoids ranged between 13-28% and 39-58%,.                                                                    during the two years under consideration, respectively. This result indicated that  some parasitoids of armored, soft scale insects and whiteflies were effective in controlling them