Abstract：The core pathogenesis of ischemic stroke complicated by type 2 diabetes mellitus （T2DM） is closely related to the theory of "sweat pores，qi-fluid，and collateral vessels" in traditional Chinese medicine. Different from pathogenesis theories such as "phlegm blended with blood stasis" or "liver-kidney yin deficiency，" the authors attempt to construct a coherent pathogenetic framework that ranges from the stagnation and obstruction of microscopic channels （sweat pores） to the damage of macroscopic collateral vessels， systematically elucidating the dynamic evolution of this comorbidity. The evolutionary pattern of the comorbid pathogenesis can be summarized into three stages： at the early stage，stagnation and obstruction of the sweat pores，leading to the disorder of opening and closing function； at the middle stage，failure of qi and fluid to disperse ，resulting in phlegm blended with blood stasis；at the late stage， toxin damaging the collateral vessels， leading to malnutrition of cerebral orifices. Stage-specific treatment should be adopted accordingly：at the early stage，open the sweat pores to ventilate and unblock the lung with acrid-dispersive medicinals；at the middle stage，eliminate stasis and resolve phlegm to promote the free flow of qi and fluid；at the late stage，remove toxins and tonify deficiency to nourish the collateral vessels. This study aims to provide new insights for the traditional Chinese medicine differentiation and treatment of ischemic stroke complicated by T2DM.