The aneurysmal bone cyst is a pseudotumoral lesion that can take several aspects. This is a rare lesion representing 1% of bone tumors. It appears usually during the first 30 years of life. The pathogenesis is that of a process of "dysplasia/hyperplasia" favored by a deficiency circulatory and hemorrhage within the lesion and the phenomena of osteoclasis. The objective of this work is to illustrate with analysis the specific forms and atypical aneurysmal bone cyst which often pose a diagnostic challenge requiring radiological investigation with histological confirmation. We report eight cases pediatric of aneurysmal cysts collected over a period of 3 years, 3 boys and 5 girls. All patients had standard radiographs. MRI was performed in three patients. The diagnosis was confirmed histologically. The atypia has been in the seat: fibula (1 case), metaphyseal (2 cases), diaphyseal (4 cases) and metatarsal (1 case). The aneurysmal bone cyst is a rare benign tumor with predilection affecting the metaphysis of long bones. Atypical forms even fewer are dominated by the atypical seat.