Litchi chinensis Sonn. is an important component of the Indian fruit basket. Its production is severely affected by the Aceria litchii mite, which induces formation of blister like galls on the leaves. GC-MS analysis of the methanolic extracts of the normal and galled leaves was carried out to study the alterations in the volatile chemical compounds in the leaf galls as a result of Aceria mite infestation. It was found that the leaves were rich in sugars, sesquiterpenes, terpenes, linoleic acid esters, vitamins, antioxidants, glycerol and steroids. Amount of Alpha methyl mannofuranoside reduced in the galled leaves to 60.82% from 72.49% in the normal leaves. Amount of Vitamin E reduced from 1.80% in normal leaves to 0.40% in galled leaves. Caryophellene increased in galled leaves (2.04%) when compared to normal leaves (0.38%). Betulinaldehyde and.gamma.-Sitosterol were absent in galled leaves but present in normal leaves (4.95% and 2.12% respectively). Lupeol and beta-Longipinene were present only in galled leaf (1.98% and 4.54% respectively) and absent in the normal leaf. The results obtained from this study show that the metabolic processes of the leaf cells have been altered by the Aceria mite, leading to changes in the chemical composition of the leaves. This study will help to elucidate the mechanism of gall formation and plant defence in Litchi, further.