CONTEXT: Ossifi cation in the human penis is such a rare condition that only 34 histologically evident cases have previously been reported. Among several conditions that have been correlated with this problem the most frequent is Peyronie disease. In all these conditions, human penile ossifi cation appears to be a metaplastic bone formation process. CASE REPORT:A 59-year-old white man presented with a one-year history of slight pain upon erection and during intercourse. He also complained of hard plaque near the base of the penis. One year earlier, he had sustained blunt trauma during intercourse. Examination of the penis revealed a fi xed fi rm mass extending over the proximal third of the penile shaft, measuring 3.0 x 3.0 x 2.0 cm and involving the corporal sponge, without surface extension. There was no impotence or other relevant clinical fi nding. Radiography on the penis revealed irregular calcifi cation in the same position as the palpable mass and in the septum of the proximal inner third of the penis. The importance of this report lies in the extent of the human penile ossifi cation, as demonstrated by the radiological and histological confi rmation.