Abstract The growth of the nasal bone from 14 to 60 days of age was studied in the midsagittal plane by a combination of X-radiography and vital staining with alizarin red S. The bone increased in length with decreasing velocity, became rounder with age and changed simultaneously its angulation with the frontal bone. The length increase was due to bone formation on both ends of the bone, while the change in shape was due to differential bone formation on the outer periosteal surface of the bone with simultaneous resorption on its nasal surface.