Serpentine foot or Z-shaped foot, definite as varus of forefoot with valgus of heel, is a deformity which is advisable to separate from metatarsus varus in children. We have studied 55 serpentine feet of 31 children aged between 6 months and 13 1/2 years, observed in 20 years. We distinguished four grades of deformities. Treatment was orthopedic in 15 times, surgical in 29, with 50% of bad result, 11 feet which haven't had any treatment were in use to indicate evolution of the adductus. However, valgus of heel is transitory and secondary to forefoot rigidity, it always regressed but growth disturbance of tarsal bone occurred making lateral deviation. We insist on early radiographic diagnosis and treatment which is orthopaedic before first year of age, then surgical when first failed or in old children. It get release of metatarsal stiffness before 6 years of age, then in older we make osteotomy of 1 degree cuneiform and cuboid to correct bone deformity. Correction of hind foot valgus, realized in 24% of the surgical treatment, must be prohibited, it always made transverse tarsal instability.