The Authors studied the postural variations of right pulmonary circulation in 30 normal subjects with rheographic technique. In lying position the rheograms remain without modifications concerning the derivations's area (superior or middle or inferior right pulmonary lobes). In standing position the rheogram of superior lobe increases his area, that of inferior lobe decreases and that of middle lobe remains unvariated. This pattern of behaviour is early modified by cardiac or pulmonary diseases. Also if this technique is easy to perform and in our experience is reproducible, we think that we must accept his limits in view of lack of a very accurate and exact calibration.