Blood turbidity and collateral disease are closely related to each other as the important component parts of the theoretical system of modern traditional Chinese medicine (TCM). The former focuses on blood and the latter on blood vessels and collaterals. By integrating these two theories, a theoretical basis for TCM syndrome differentiation and treatment of modern diseases can be provided. This article summarizes the correlation of origin, concept, treatment method and representative drugs of two theories, and points out that both blood turbidity and collateral disease prospers and develops through the integration of TCM classical theory and modern medical achievements. Theoretically, blood turbidity is the cause of collateral disease, and collateral disease is the result of aggravated blood turbidity. In many metabolic diseases, blood turbidity and collateral disease actually correspond to the main features of the early and late stages of the same disease, respectively. In treatment, clearing blood turbidity is consistent with dredging collaterals. When clearing blood turbidity, it is necessary to dredge the collaterals, and when dredging the collaterals, it is necessary to clear the blood turbidity. In terms of prescription and medication, Huazhuo Xingxue Decoction is the representative prescription of blood turbidity, which can be combined with Ramulus Cinnamomi, Sichuan lovage rhizome, earthworm, and other dredging collateral drugs. The representative prescription for collateral disease is Tongxinluo Capsule, which can be combined with lotus leaf, Fructus Crataegi, cassia seed, and other turbid-clearing drugs to enhance the curative effect.