Solitary bone cyst is a benign bone tumor found in the metaphyseal region of long bones, such as proximal humerus and proximal femur in the growing period.

The Occurrence of the solitary bone cyst on the distal humerus associated with nonunion of fracture is rare.

The etiologies are variously proposed, so multiple modalities of treatment are available.

The authors experienced a case of solitary bone cyst accompanied by nonuion of lateral condyle of humerus, which received satisfactory surgical treatment of curettage and bone graft along with Internal fixaiton.

Finally healing of solitary bone cyst and osteosynthesis was achieved.