To evaluate the diagnostic value of combination of D-dimer and Doppler Intima-Media Thickness (IMT) based on clinical data for vascular dementia (VaD). In this study, 100 cases of initial VaD were diagnosed by Zhenjiang Fourth People Hospital as VaD group, and 100 healthy were engaged as control group, medical history and test results were collected for evaluation. IMT and D-dimer were highly correlated with the onset of VaD. The sensitivity of combination diagnosis for early VaD: 90.2%, the specificity: 87.9%, the area under the curve (AUC) is 0.872, which were superior to IMT or D-dimer alone. D-dimer and IMT are significantly increased in the initial onset of cerebrovascular diseases, and combined detection of them is conducive to early diagnosis and evaluation of the disease. Given the limitations of D-dimer and IMT, combined detection is more conducive to early diagnosis and prognosis, and can be used as screening and routine examination items, even evaluate the severity of cognitive decline.