Diabetes mellitus is a common long-term, chronic disease, which simply means that the increase in serum glucose causes damage to various tissues and organs of the body. The typical symptoms of the disease are eating more, drinking more and urinating more, but losing weight, which is often referred to as “three more and one less”. There are four types of diabetes, namely type 1 diabetes, type 2 diabetes, gestational diabetes and special types of diabetes, among which gestational diabetes is mainly related to changes in hormone levels during pregnancy, while special types of diabetes may be related to genetic mutations. The cause of type 1 and type 2 diabetes is not well understood and may be related to poor lifestyle habits and genetic factors. The diagnosis of the disease is relatively easy and is mainly based on fasting blood glucose values and glucose tolerance tests to confirm the diagnosis. Diabetes mellitus is more prevalent in China and can cause a variety of complications when the blood glucose is not well controlled for a long time, which can harm all organs of the body. The treatment measures for this disease are mainly diet, exercise, diabetes education, disease monitoring and medication, and medication is divided into two kinds: injection medication and oral medication.