Women with vulvar lichen sclerosus (LS) have an increased risk of developing differentiated vulvar intraepithelial neoplasia and vulvar squamous cell carcinoma (SCC). Our primary aim was to determine the prevalence of LS among women with vulvar SCC. All patients who underwent excision for invasive SCC of the vulva from January 1, 2009 to December 31, 2013 were identified by searching our institution’s electronic laboratory information system (n=111). The vulvar excision specimens from these patients were reviewed for the presence of adjacent LS. The grade of the SCC and clinical data were also documented for each case. The proportion of vulvar SCCs with adjacent LS identified on the excision specimen was 0.29 (95% confidence interval, 0.21–0.38). The proportion of patients in our study population who have ever had a histopathologic diagnosis of LS was 0.36 (95% confidence interval, 0.28–0.45). The presence of LS was not associated with the grade of the adjacent SCC. Patients with synchronous LS on excision were older on average than patients without LS. Tobacco users in our population were more likely to have a history of lower genital tract dysplasia, more likely to be younger, and less likely to have LS identified on the vulvar SCC excision specimen. Given the strong association between LS, differentiated vulvar intraepithelial neoplasia, and vulvar SCC, we recommend careful evaluation of these patients from a clinical and pathologic standpoint.