In today's society, the incidence of diabetes is getting higher. It can cause a variety of complications and endanger human health. How to safely and effectively reduce blood sugar has become a hotspot of concern. Konjac dietary fibre is one of the most excellent soluble dietary fibres found so far. Its health benefits include weight loss, lowering blood fat and blood sugar, and it has a laxative effect. This article mainly reviews the clinical observations, related mechanisms of action, appropriate dosages and toxic side effects, providing a basis for the clinical application of konjac dietary fibre and proposing a new mechanism for its hypoglycaemic effect. It provides new ideas for the research and development of konjac in the prevention and treatment of diabetes.