The article addresses the consequences caused by radiotherapy in the oral cavity, which involves ionizing radiation to combat tumor cells. Radiotherapy can be associated with other methods, such as surgery and chemotherapy, and aims to eliminate the tumor without affecting nearby normal structures and functions. However, radiotherapy can also generate side effects on normal cells, especially in the oral cavity, causing oral sequelae. Oral sequelae are changes that harm patients' health, nutrition, speech, chewing, swallowing, breathing, aesthetics and self-esteem, in addition to interfering with treatment, causing infections, bleeding, osteoradionecrosis, necrosis, fibrosis, trismus, cavities, tooth loss, among other complications. Therefore, the text proposes a literature review on the oral sequelae of radiotherapy in the oral cavity, to identify the main oral changes, evaluate patient satisfaction and suggest strategies for preventing and controlling oral sequelae.