Persistent genu valgum in adolescent induce abnormal gait and functional disturbances. Surgical correction should prevent secondary osteoarthritis. MATERIAL AND METHODS: Twenty three percutaneous epiphysiodesis in 12 children are reviewed at the end of growth. The surgical technique and the X-ray evaluation and timing calculation of epiphysiodesis according to Bowen are described. RESULTS: The supine intermalleolar distance is reduced from 11.8 cm to 2.8 cm. The femoro-tibial angle is reduced from 12.9 degrees to 7.9 degrees and distance between mechanical axis and center of knee from 25.3 mm to 8.6 mm. These results are very good, without any complications. DISCUSSION: Percutaneous epiphysiodesis is really a mini-invasive and cost effective method for treatment of genu valgum. The results are at least as good as in Blount stapling without any complication or second surgery for hardware removal. The timing of epiphysiodesis remain a difficult problem and the physician should be very cautious in determining the good time for surgery. CONCLUSION: Percutaneous epiphysiodesis is today the treatment of choice for genu valgum. This method is non invasive and cost effective.