This study examines the interaction effects among incidences of falls, visual conditions, and stance postures on the magnitude of center of pressure sway (MCOPS) in patients with schizophrenia. The coordinates of COP in ten postural control demands were measured in subjects with at least one or without any falls in the previous year. MCOPS was calculated by the default program in Balance 3.78 software. Cognitive functions were also measured. The findings include: (1) the MCOPS increased as the postural control demands increase in subjects who have fallen; (2) MCOPS in subjects without falls was the largest for the lowest postural control demands; (3) MCOPS increased when the eyes were closed in subjects without a history of falls but decreased in subjects with a history of falls; (4) cognition function in subjects who have fallen was inferior to that in those without falls. The interference visual condition and stance postures on MCOPS tended to be different in schizophrenia with or without incidences of falls indicating the possible association between psychomotor dysfunction and falls in the subjects.