Oral lichen planus (OLP) is a chronic inflammatory mucocutaneous disease of unknown etiology. OLP has recently been linked to thyroid disease, mainly hypothyroidism. The aim of this study was to determine the prevalence of thyroid disease in Colombian patients with OLP. A total of860 clinical records of patients attending the clinics of oral medicine and oral and maxillofacial surgery at IPS CES Sabaneta, Colombia, between 2010 and 2016 were reviewed. Fourteen patients (1.6%) had a diagnosis of OLP. The prevalence of hypothyroidism in patients with OLP was 35.7%, compared to 3.95% in the entire study population (OR 15.92, 95% CI: 5.63-50.09, P = 0.0001). Patients with concomitant hypothyroidism and OLP presented with less severe oral lesions compared to those without thyroid disease. This study supports the notion that patients with OLP should be screened for thyroid disease.