Oral changes following radiotherapy are not uncommon. Oral mucositis, alteration in salivary gland function, radiation caries, and gingival changes have all been reported following radiotherapy and chemotherapy. The gingival changes seen after radiotherapy may be unusual and often cause diagnostic dilemma. Metastasis to the gingiva has also to be ruled out in these cases. A 30-year-old female patient presented with enlargement of the gingiva of 6 months’ duration and lower lip swelling of 7 months’ duration. She was a known case of carcinoma of nasopharynx and had received radiotherapy and chemotherapy. Based on the history, the clinical appearance of the gingiva, and the other oral changes we considered both post-radiotherapy gingival enlargement and secondary metastasis to gingiva as possibilities. An incisional biopsy was performed (internal bevel gingivectomy). The histopathological report did not reveal any metastatic changes. Thus, we diagnosed post-radiotherapy gingival enlargement. For the multiple carious teeth, extraction and root canal treatment was carried out as necessary. The patient was referred to the department of Oral and Maxillofacial Surgery for management of swelling of the lips, which was diagnosed as lymphedema of the lip. Gingival enlargement is rare post radiotherapy. Such nonplaque-associated gingival enlargement in a patient who has undergone radiotherapy should be subjected to biopsy and histopathological examination to distinguish between secondary metastasis and post-radiation changes.