A case of congenital short femur in an otherwise healthy infant is described. Antenatal sonographic diagnosis was made at 26 weeks of gestation. The left femur was shorter than the right (ratio 0.82-0.85). In this case, the occurrence of congenital short femur was sporadic. The diagnosis was confirmed after delivery. This case illustrates the importance of ultrasound as an early detector of certain congenital anomalies and as a useful tool in their follow-up.