The mango aphid, Aphis odinae (Toxoptera odinae) (Van der Goot) (Hemiptera: Aphididae), is an occasional, phytophagous sucking pest of mango. These aphids are very often associated with natural enemies and an ecological understanding, especially on insect—crop relationships, is needed in management. This will be manifested in altered sugar and amino acids contents of the plant. In light of this, the effect of aphid feeding on the content of total soluble sugars (TSS) and free amino acids (FAA) in mango shoots was studied. The amount of TSS and FAA in infested and uninfested shoots with varying levels of aphid infestation, namely low, medium and high, were quantified. Results indicated a significant reduction in the amount of TSS and FAA in infested shoots due to aphid feeding (P < 0.05). At maximal aphid abundance (251–300 aphids/shoot), TSS declined by 32 % and FAA by 47.5 %. Further, regression analysis between aphid numbers and the quantity of TSS/FAA yielded simple linear equations with R² = 0.99, which can be used as an alternative way to estimate aphids numbers. The present study discusses the influence of aphid herbivory in mango shoots, a critical factor in understanding aphid–plant interactions and their damage to the host. It can be possibly extended to similar other aphid infestations.