Experiments were carried out to evaluation effectiveness of different infestation levels by oleander aphid, Aphis nerii (Boyer) (Aphididae:Hemiptera) on quantity and quality of the internal components of important cactus-plant, Usher Milkweed Calotropis procera (Ait) (Fam:Asclepiadaceae). Experiments were carried out at two different locations; Giza and Alexandria Governorates during season 2022. Infestations by A. nerii during successive seasons were classified into three levels: low, medium and high (due-to mean population number of aphid). Internal components of cactus leaves were: cardiac-glycosides, usharin, ushardin, calotoxin, calctin, calotropagenin, trypsin, proteoclastic-enzyme alpha-calotropeol, beta-calotropeol, giganteol and iso-giganteol. Data obtained in both of two locations showed that the low infestation by A. nerii on C. procera affected on concentrations of the internal components of C. procera leaves compared-to control (healthy leaves) and medium infestation treatments had higher effect than low-infestation and control treatment. Further, high-infestation had greater effect than both of low and medium infestations. Quantity of usher Milkweed (latex) decreased in cactus-trees infested by A. nerii compared-to control in this descending order; high, medium and low infestation at both of twolocations. Concentrations (i.e. quality) of internal components of C. procera leaves significantly varied among levels of infestations including those of free-infestation level and quantity of usher Milkweed (latex) significantly differed as well.