We estimated the correlation dimensions (D2) and the largest Lyapunov exponents (LI) of EEGs during resting, acoustic white noise and music periods in schizophrenia patients to investigate the dynamical properties underlying the EEG. We recorded the EEG from 21 schizophrenic and 21 age-matched healthy subjects at anterior frontal regions. The schizophrenia group had a lower LI at the left frontal region compared with controls during all the periods of the procedure (p<0.05). Also, increase in LI was clear for only schizophrenia group during the two auditory stimuli periods at left frontal region. These suggest that to investigate the underlying dynamics of emotional states in schizophrenics brain by nonlinear analysis, LI might be a useful tool.