Lung cancer, including non-small cell lung cancer, remains prevalent in Australia and has a very poor survival rate. Metastases to the oral cavity are a rare occurrence that can arise from lung cancers. This case report describes the presentation of a metastatic lesion from a poorly differentiated lung adenocarcinoma on the mandibular buccal alveolar attached gingivae. The inpatient had terminal disease with known pleural, brain and liver metastases and was receiving palliative care at the time of diagnosis of the oral lesion.Keywords: Adenocarcinoma, cancer, oral metastasis.Abbreviations and acronyms: ALK = anaplastic lymphoma kinase; CT = computed tomography; EBUS = endobronchial ultrasound scan; EGFR = epidermal growth factor receptor; IHC = immunohistochemistry; MRI = magnetic resonance imaging; NSCLC = non-small cell lung cancer.