Introduction: As one of the most common human malignancies, oral and oropharyngeal cancer represents a challenge in global public health. Objective: To describe the lesions diagnosed during an oral cancer prevention campaign carried out in Fernandópolis, Brazil, in 2018. Material and methods: Patients treated at the basic health units in Fernandópolis on the day of the campaign were examined by a previously trained dentist who looked for suggestive oral lesions with malignant potential. Patients with suspicious lesions were scheduled for re-evaluation by an oral disease specialist to obtain the correct diagnosis of the lesion. Results: 956 patients were examined during the campaign. Among them, 75 (7.84%) were referred, however, 66 (88%) attended for reassessment and proper diagnostic management by the dentist specializing in oral diseases. Were diagnosed 59 benign oral lesions and 23 variations from normality, no patient was diagnosed with malignant oral lesion. Conclusion: The absence of a diagnosis of oral cancer during the campaign suggests the need to reassess its methodology, aiming to reach a target audience with a higher risk of carrying oral lesions that lead to malignant manifestations. It is also noteworthy that health professionals need better training to clinically recognize lesions suggestive of oral cancer.