In this study we present a rare case of peripheral desmoplastic ameloblastoma and discuss its clinical features, histopathology, and immunohistochemical profile. This article reports a new case of this unusual neoplasm in a 66 year-old woman in which the main complaint was an asymptomatic swelling located in the right body of mandible. Histopathological findings were similar to the two previously reported cases of this tumor. Positive immunohistochemical stain for laminin V and type IV collagen suggests an inductive effect of the epithelium over the stroma while the low index of p53 protein and Ki-67 expression in epithelium and stromal cells, as well as CD138 uniform positive-stain in epithelial cells, support the benign biological behavior of this lesion. Including this new case, currently there are only three reports of this rare neoplasm. Reports of new cases of peripheral desmoplastic ameloblastoma are necessary for a better understanding of the origin and behavior of this particular subtype of ameloblastoma.