Purpose: To evaluate the hypoglycaemic activity of the ethanol extract, chloroform fraction, and three compounds isolated from Premna latifolia. Methods: The ethanol extract, chloroform fraction, and compounds 1 – 3 (isolated from the chloroform fraction) of P. latifolia were characterised by nuclear magnetic resonance (1H NMR,13C NMR and 2D NMR). In vitro activity was assessed by α-amylase and α-glucosidase inhibitory activity assays. In vivo antidiabetic activity was evaluated in a streptozotocin-nicotinamide-induced rat model of diabetes. Fasting blood glucose (FBG), glycosylated haemoglobin (HbA1C), serum creatinine, blood urea nitrogen (BUN), liver enzymes, and antioxidant enzymes were determined. Liver and pancreas histopathology was assessed. Results: Compounds 2 and 3 exhibited significant hypoglycaemic activity by reducing elevated FBG and HbA1C (p ≤ 0.001) and also exerted positive effects on blood and liver enzyme profiles, which were largely altered in diabetic control group. These compounds also showed significant antioxidant activity, increasing catalase, superoxide dismutase, and glutathione reductase, while lowering malondialdehyde (p ≤ 0.001). The histopathology results for the rats that received these compounds suggested regeneration of pancreatic β-cells. Conclusion: Compounds 2 and 3 isolated from the dried roots of P. latifolia possess significant hypoglycaemic activity, reno-and hepatoprotective effects, and antioxidant activity. They show promise as potential treatments for patients with diabetes. © 2018 The authors.