Ossifying Fasciitis (OF) is a soft tissue benign tumor with rare occurrence, that affect most commonly the trunk and extremities with infrequent head and neck involvement. It is considered as a form of nodular fasciitis with similar clinical behavior but different histological findings. It can mimic malignant lesions due to its behavior and reactive characteristics. Ossifying fasciitis affect adults more commonly, and rarely affect children. The primary symptom of ossifying fasciitis has been described as local inflammation associated with pain, but asymptomatic presentation has also been reported. We herein present a rare case of a 19-months-old boy, with history of a rapidly growing hard painless swelling at the right side of the mandible. Resection of the mass, and a subsequent correlation with histopathological and radiological findings resulted in the final diagnosis of ossifying fasciitis affecting the submandibular region at the lower boarder of the mandible. Recovery was uneventful, with more than five-years follow-up showing no sign of recurrence. Despite the resemblance of to malignant lesions, accurate clinical and histopathological examination is crucial to avoid misdiagnosis and consequently unnecessary aggressive treatment.