This living systematic review aims to summarize evidence on the prevalence of oral signs and symptoms in patients with COVID-19 . The review was reported per the PRISMA checklist, and the literature search was conducted in 6 databases and in gray literature . Studies published in any language mentioning oral symptoms and signs in patients with COVID-19 were included . The risk of bias was assessed by the Joanna Briggs Institute appraisal tools . The certainty of evidence was evaluated through GRADE assessment . After a 2-step selection , 40 studies were included : 33 cross-sectional and 7 case reports . Overall, 10,228 patients (4,288 males, 5,770 females, and 170 unknown) from 19 countries were assessed . Gustatory impairment was the most common oral manifestation, with a prevalence of 45% (95% CI , 34% to 55% ; I2 = 99 %). The pooled eligible data for different taste disorders were 38% for dysgeusia and 35% for hypogeusia, while ageusia had a prevalence of 24% . Taste disorders were associated with COVID-19 (odds ratio [OR], 12.68; 95% CI , 6.41 to 25.10; I2 = 63% ; P <0.00001), mild/moderate severity (OR , 2.09; 95% CI , 1.25 to 3.49; I2 = 66% ; P = 0.005), and female patients (OR , 1.64; 95% CI , 1.23 to 2.17; I2 = 70% ; P = 0.0007). Oral mucosal lesions presented multiple clinical aspects, including white and erythematous plaques, irregular ulcers, small blisters, petechiae, and desquamative gingivitis . Tongue, palate, lips, gingiva, and buccal mucosa were affected . In mild cases, oral mucosal lesions developed before or at the same time as the initial respiratory symptoms; however, in those who required medication and hospitalization, the lesions developed approximately 7 to 24 d after onset symptoms . Therefore, taste disorders may be common symptoms in patients with COVID-19 and should be considered in the scope of the disease's onset and progression . Oral mucosal lesions are more likely to present as coinfections and secondary manifestations with multiple clinical aspects (PROSPERO CRD42020184468).