Anticarsia gemmatalis is one of the most significant insect pests of the soybean crop. Despite its herbivorous habits little is known about the importance of enzymes involved in the digestion of carbohydrates to insect biology. The aim of this work was to investigate the carbohydrases of the velvet bean caterpillar reared on soybean leaves and standard artificial diet. Fifth-instar larvae were collected and cold immobilized prior to dissection. The whole gut was removed, homogenized in 100 mM citrate-phosphate buffer, pH 5.0, and centrifuged at 10,000 g for 5 min. The supernatant was collected and used for hydrolases assays and activities were tested against seven different substrates. Differences were found in digestive enzymes between natural and artificial diets. For larvae reared on leaves, the highest activity was seen against maltose (29.0 mU/gut) followed by lactose (10.2 mU/gut), and p-nitrophenyl-b-D-galactopyranoside (7.6 mU/gut). Activity also detected against the other substrates tested. No significant carbohydrase activities were detected in the gut of larvae fed on artificial diet, except for a-glucosidase probably due to the presence of beans in the composition of the diet. Plate assay was used to detect cellulase, pectinase and xylanase production. A higher production of pectinase and cellulase was detected when gut extracts from leaves-fed larvae were used in comparison to insect reared on artificial diet. No xylanase was produced irrespective to diet employed. These results show that A. gemmatalis is able to modulate carbohydrases levels in accordance with diet type.