When dissimilar figures are presented to the two eyes individually, perception alternates spontaneously between each monocular view. This phenomenon, designated binocular rivalry, has been used by many scientists as a tool for investigating visual awareness. Some recent studies have suggested involvement of serotonergic neural systems in this phenomenon. We explored the relationship between binocular rivalry and anxiety, a state thought to be associated with serotonergic neural activity. Perceptual alternation rate in dominance of binocular rivalry were compared between normal volunteers with high and low general anxiety as measured using the harm avoidance (HA) scale of the Tridimensional Personality Questionnaire. Perceptual alternation rate and rhythmicity in the high-HA group was significantly greater than that in the low-HA group. The perceptual alternation rate in binocular rivalry was accelerated in anxious subjects, suggesting that binocular rivalry and anxiety may share some common serotonergic neural substrates.