According to literature review, oral metastatic tumors account for approximately 1% of oral malignancy. Most of these primary malignancies arise from the locations below the clavicle. Lung, breast and kidney are the most frequent sites. Metastatic tumor may occur in the soft tissues or in the jawbones. Rapid growth gingival mass, destruction of jawbones, pain or paresthesia are the common clinical manifestations. In this article, we will present a case with initial chief complained of rapid growth mass over upper and lower gingivae. Non-small cell lung cancer with oral metastasis was diagnosed after comprehensive systemic review. Clinical presentation of oral metastatic tumor with its possible mechanism and treatment will be discussed in this article.