Mediterranean fruit fly, Ceratitis capitata (Wied.) is a serious horticultural insect pest in Egypt, Mediterranean basin and many countries of the world. Licorice, Glycyrrhiza glabra L. is a plant growing in Egypt and many other countries and famous for saponins groups that have insecticidal effect against broad spectrum of insect pests. Licorice roots aqueous extract (LRAE) 1150, 700 and 300 ppm/l were tested for the insecticidal effects against C. capitata full-grown larvae and different pupal ages (one, three, five and seven day old pupae) by dipping for 30 and 60 seconds. Dipping treatment in LRAE for 60 seconds decreased the tested stages of C. capitata more than 30 seconds treatment. Full-grown larvae population was suppressed by 99.33% after larval dipping in LRAE 1150 ppm for 60 seconds. Based on toxicity values, three days old pupae were the most responded pupal age to LRAE dipping treatments for 60 seconds with LC₅₀ 1.5×10¹ and LC₉₀ 1.80×10² ppm/l. Histological studies cleared that larval tissues were affected externally and internally after treatment with LRAE. Emerged flies were not able to either feed or move normally. The histological studies of flies showed that mouthparts, the maxillary palps, foregut neuropil areas, and tracheal tubes were severely affected. The treated flies female ovaries and male testis showed normal view of tissues. Phytochemical screening of powdered licorice roots methanolic extract proved presence of phenols, flavonoids, terpenoids, saponins, tannins and steroids compounds. Saponins compounds were the major constituent of licorice roots methanolic extract.