Osteoma originated from paranasal sinus is relatively rare neoplasm but this is the most commonest benign tumor to be seen in paranasal sinuses. Osteoma are classified as compact, cancellous or mixed. Excision of the tumor is indicated when it is large or producing symptoms. The many suggested site of origin are as varied as the theories of pathogenesis. Recently, a 55-year-old male who had osteoma in the left ethmoid sinus was observed. This is the report of the case with review of the literature.