In the study, administration of andrographolide for 8 days succeeded to decrease the postprandial and preprandial blood glucose levels in comparison to those of the control. An improvement of diabetic rat islets, beta cells (morphology and density) and pancreatic insulin contents were also found after treatment with andrographolide. Glibenclamide, an type 2 antidiabetic drug acting to stimulate insulin-releasing beta cells (pancreatic action), also showed similar effects on the pancreas. Glibenclamid could improve the diabetic rat islets, beta cells and pancreatic insulin contents. In the other side, AEEAP decrease the blood glucose levels mildly. Only moderate changes in Langerhans islets, beta cells and pancreatic insulin were shown after AEEAP treatment. Based on these results, it indicates that andrographolide as a single compound is more effective than in the form of AEEAP in neonatal streptozotocin-induced diabetic rats.