30 years of research in the area of oral cancer in the State of Paraná-Brazil teaches us that prevention and information are the only ways to reduce oral cancer. high rate of lip lesions of solar etiology and lesions of the oral mucosa has been observed. (mainly in patients who drink alcohol, use tobacco and exposure to the sun). In addition to health actions beginning in 1989 and 2000, a pre-screening center for oral injuries was created in Curitiba before referring to the tertiary center, in order to decrease the volume of patients without the need for specialized care that was sent to that center. In 31 months, 1.316 biopsies were performed in patients who would not need tertiary treatment, that is, patients from the pre-screening center, and 37 confirmed malignant tumors were found. In order to stimulate prevention due to the high number of injuries found, professionals from all over the state of Paraná received training to assist patients and assisted in a single day of 2002 for the prevention of oral cancer. The result of this was: 7.638 clinical examinations, with 1.522 injuries (22.6%). Due to the success and adherence of professionals in the project, we continued with these health actions. In 2013, 25 years of oral cancer prevention has been completed, which, over that period, resulted in 22.300 patients with a high rate of mouth injuries found. This encouraged continuing with these health actions. In state, We have observed a regression in the estimate of oral cancer for the period from 2020 to 2022 by the National Cancer Institute (INCA). Preventive actions for oral cancer are the key to success.