OBJECTIVE: To study the effect of self-setting calcium phosphate cement (CPC) on the repair of local bone defects after resection of cyst in children. METHODS: From December 1998 to May 2002, 22 patients with bone defects were repaired with CPC. Their ages ranged from 4 to 10 years with an average of 8.3 years. There were 11 cases of non-ossifying fibroma, 7 cases of osteoid osteoma, 2 cases of bone cyst and 2 cases of fibrous dysplasia. The bone defects are located as the following: femur in 14 cases, tibia in 6 cases and humerus in 2 cases. CPC spongiosa granules were filled in 11 cases, injectable CPC were filled in 2 bone cyst cases. The patients were followed up for 5-48 months, averaged 23.5 months. RESULTS: Bone matrix grew well and no recurrence was found. CONCLUSION: The method with simple CPC in repairing bone defects is safe, non-toxic, economic and convenient in children.