Chondroblastoma is a relatively rare benign bone tumor. This is a case of a chondroblastoma in the calcaneus which was removed successfully by curettage and replaced with a bony substitute of calcium sulfate pellets impregnated with autologous bone marrow. After two years, the patient remained symptom-free, and the radiographs demonstrated complete fi lling
of the defect with good bony union without recurrence.