Property and flavor theory of traditional Chinese medicine (TCM) is the core base for clinical treatment of diseases. However, few research about its chemical and biological characterization was performed. In this paper, network pharmacology was adopted to review patterns around the theory of TCM. “Xiaoke” prescription database, which combinations of herb medicines for diabetes therapy, was firstly built to explore prescription regularity and screen core paired-components. The prescription regularity and molecular mechanism of flavor composition were explored through the relationship of “drug-compound-target-pathway-function” by ChEMBL, CTD and KEGG datebase. As a result, the tastes of “Gan” (sweetish taste) and “Ku” (bitter taste) were the popular therapeutic flavor to regulate the disorder of glucose and lipid metabolisms. The mechanism of Xiaoke was summarized from representative traditional Chinese medicine partner “Zhimu-Huangbai” and “Huangqi-Gegen”. The key components of “Gan”, including saponins stimulated insulin secretion, improve insulin resistance and promote glucose utilization. The components of “Ku”, including flavonoids and alkaloids regulate inflammatory cytokines, promoted the utilization of glucose, improve endocrine and metabolism through MAPK, PI3K-Akt, PPAR signal pathway. The TCM therapeutic mechanism about “Xiaoke” was preliminarily summarized to clear “heat” by anti-inflammation and immunoregulation, to regulate glucolipid metabolism for removing the satiation of digestion, and to improve the utilization of insulin and diabetes complications for endocrine adjusting. The results demonstrate that therapeutic principle of TCM for “Xiaoke” is comprehensive via multi pathway. This study provides a new research method and strategy for exploring the mechanism of TCM for diabetes therapy.