To help determine whether ocular torticollis causes facial asymmetry, we analyzed photographs of patients with long-standing head tilts for amounts of tilt and facial asymmetry. Significant facial asymmetry that correlated with the side of the head tilt was found in patients with congenital superior oblique muscle paresis, but not in patients with traumatic superior oblique muscle paresis nor in patients with dissociated vertical deviation. The mechanism explaining the development of facial asymmetry in these patients may be deformational molding of the face and skull from the infant's sleeping with its head turned predominantly to one side during the first 6 to 12 months of life. Early strabismus surgery to correct the head tilt may help prevent facial asymmetry, but ensuring that the infant sleeps with alternating head positions may be more important.