To decrease the prevalence of orthostatic hypotension in patients taking antipsychotics 62 pchizophrenics' blood pressure and heart rate were measured at different posture. The data showed that the systolic pressure, diastolic pressure and heart rate in supine position were statistically different from those at standing position (P < 0.01). In standing position the heart rate was 41/min higher, the systolic pressure 1.32 kPa lower and the diastolic pressure 1.2 kPa higher than those in supine position. The systolic pressure of 5 cases were normal in supine position and under 12 kPa in standing position. It is concluded that the heart rate and blood pressure should be measured both in standing and supine position in patients taking antipsychotics, so as to prevent the onset of orthostatic hypotension.