Immunoglobulin G (IgG) anti-GD1a ganglioside antibody is an important marker of Guillain-Barré syndrome (GBS). This antibody is highly associated with disease severity, the need for mechanical ventilation, and axonal degeneration of peripheral nerves. We report a 46-year-old female patient manifesting the IgG anti-GD1a antibody with polycranial neuropathy and sensory ataxia as a variant of GBS. She presented with slurred speech, swallowing difficulties, and gait disturbance following diarrhea. Decreased sensations of vibration and position were found in her distal limbs and she had an ataxic gait with a positive Romberg sign. Her serum was positive for IgG anti-GD1a ganglioside antibody (1:640). Her neurological examination at the third month after intravenous Ig treatment showed complete recovery.