Laboratory studies under constant temperature of 27±2oC and 65±5 RH were carried out in the insectary of Economic Entomology Department , Faculty of Agriculture, Mansoura University to develop an artificial diet for rearing two coccinellid predators species Coccinella 9-punctata L and Chellomens propinqua nilotica (Mulsant). The results showed that the average duration of the predatory species, C. 9-punctata L. larval stage lasted 17.22±1.75 days, when fed on the cotton aphid, Aphis gossypii Glover, and the average total larval consumption was 734.2±10.65. The pupal stage lasted 6.75±0.85days. The predator,s female consumed a total average of 2888.79±67.54 and the number of deposited eggs per female averaged 1117.0 eggs. The predator male consumed a total average of 1765.23±29.5. Obtained data of Ch. propinqua nilotica larvae lasted 13.73±1.12days when fed on A. gossypii. Average total laval consumption reached 468.39±21.6. The predator,s female consumed a total average of 2022.45±55.6 aphid individuals . The number of deposited eggs per predator female averaged 913. ±11.5 eggs. The predator male consumed a total average of 1136.02±38.4. Obtained results of the two coccinellid predatory species when reared on an artificial diet, showed the average durations of  larval stage lasted 22.15±2.4 and 18.38 ±1.96 days for C. 9-punctata and propinqua nilotica, respectively . Respective fecundity of the females of the two species  was 360.62±14.8 and 325.8±11.5 eggs respectively. The results assured that the two predatory species  reared successfully on this artificial diet.