Solitary fibrous tumor (SFT), which was initially believed to be a subtype of mesothelioma, has been reported to occur outside the pleura. In the head and neck region, it primarily manifests in the oral or nasal cavity, with rare occurrences in the facial region. A 40-year-old woman visited our hospital with a mass on her chin. Prior to surgery, involuntary movement was observed in the ipsilateral corner of the mouth upon palpation of the mass. Special care was taken during the surgical procedure to avoid damaging the facial nerve. The mass was excised, and histological examination and immunohistochemical analysis confirmed the diagnosis of an SFT. Here, we present the first reported case of an SFT diagnosed in a jaw mass in Korea. The objective of this study was to highlight the importance of the diagnostic accuracy of SFTs in lower jaw masses.