A Collagenous Fibroma (Desmoplastic Fibroblastoma) is a rare, benign, slowly growing, fibroblastic, soft tissue lesion. Here, the case of a 28-year-old woman, who presented with a 1-year history of a slowly growing painless mass in the right anterior aspect of her neck, is described. This type of tumor was first described by Evans in 1995, and named as a Desmoplastic fibroblastoma but was renamed, by Nielsen in 1996 as a Collagenous Fibroma. This type of tumor is frequently reported in men with a mean age at occurance of 50 years. Clinically, a Collagenous fibroma presents as a firm, well-circumscribed subcutaneous, or intramuscular, painless mass of long duration. They are mostly located in the neck and extremities. The tumors range in size from 1 to 20 cm and predominantly occurs within the subcutaneous tissue, but fascial and skeletal muscle involvement is common. The treatment of a Collagenous Fibroma is a total surgical excision. No tumor recurrence has been reported the literature during the follow-up period and no tumor recurrence was observed in our case at the 1-year follow-up.