Abstract: The diabetic cognitive impairment (DCI) starts insidiously and can further develop into dementia. Early prevention and treatment are the key measure. "Turbidity" refers to the body's metabolic products or the substances that cannot be transported and transformed normally, which is the breeding ground for DCI. The improper diet of diabetes patients leads to the imbalance of spleen and stomach absorption and induces the accumulation of essence into sugar turbidity. When the turbid remains for a long period of time, it will turn into phlegm, stasis, and turbid toxins and damage the clear orifice, resulting in cognitive impairment, which belongs to the category of "turbid evil invading the clear orifice". Neuroinflammation is a key factor inducing DCI, which is mainly regulated by metabolic reprogramming. As the direct product of metabolic reprogramming, lipid and lactate accumulation are key mediators of neuroinflammation, along with high glucose, belonging to the category of "turbid evil" in traditional Chinese medicine. Metabolic reprogramming in the microenvironment of diabetes induces lactate and lipid accumulation, and mediates neuroinflammation, which is quite consistent with the development of TCM pathogenesis of "turbid evil invading the orifices". This paper aims to explore the modern biological understanding of the pathogenesis of turbid evil invading the clear orifice in DCI from the perspective of metabolic reprogramming, and to provide new ideas for its research of prevention and treatment in traditional Chinese medicine.