BACKGROUND AND PURPOSE: This is a report of a patient with diplopia, hypertropia, extorsion and a positive Bielschowsky Head Tilt Test following retrobulbar anesthesia, due to an inferior oblique muscle overaction-contracture. CASE REPORT: Oculomotor and sensorimotor examinations and ocular motility recordings and Bielschowsky Head Tilt Test demonstrated overaction characteristics overpowering the contracture characteristics of the involved inferior oblique muscle. RESULTS: Weakening of the overacting inferior oblique eliminated the vertical and torsional deviations and the forced head tilt difference upon tilting the head to either shoulder. It also normalized ocular motility and resulted in a symptom-free patient. CONCLUSION: Oblique muscle dysfunction with vertical and torsional deviations and a positive Bielschowsky Head Tilt Test can result from retrobulbar anesthesia.