Recently, we encountered a man with isolated bilateral sixth nerve palsies and areflexia whose titer of anti-GQ1b IgG antibody was elevated. We propose that bilateral sixth nerve palsies can be the sole manifestation of "anti-GQ1b antibody syndromes" and that patients with isolated bilateral sixth nerve palsies should be administered an anti-GQ1b antibody test for the diagnosis of acute immune-related neuropathy.