The study used high-frequency ultrasound to characterize the vulvar skin in patients with lichenoid vulvar dermatoses (LVD) and to assess the correlation of sonographic vascular index (VI) with histopathological microvessel density (MVD) and microvessel area (MVA). A group of patients with LVD was compared with a control group of 35 healthy women matched for age and BMI. Analysis showed significantly increased thickness of the epidermis, subepidermal low echogenic zone (SLEB), dermis, and VI in the LVD group (all P < 0.05 versus control). Correlation analysis showed a positive association between VI and MVD (r = 0.438, P < 0.05) as well as between VI and MVA (r = 0.630, P < 0.05). Vulvar skin thickness and VI are higher in LVD patients than in controls. VI reflects microvascular status in LVD. High frequency ultrasound is of significant value in the evaluation of LVD.