The spatial distribution law of rainfall and temperature in winter and summer over LRGR was studied with corresponding rainfall and temperature data and general circulation data. The results indicated that the LRGR mean winter rainfall longitudinally distributed along river, while the unique topography of LRGR did not obviously have impact on the winter rainfall; the winter temperature distribution was like belt, which decreased from low latitude to high latitude; the passing obstructing effect of LRGR cannot be clearly showed with the winter temperature distribution; but such effect is obvious over Nuvalley and Lancang-valley. The distribution of LRGR summer mean rainfall was determined by the obstructing effect and two stronger ascending airflow that come from Bengal Bay and South Sea and converge around corresponding windward slopes；the general circulation distribution in meridional section is equal, which showed the passing effect of LRGR. The passing-obstructing effect led the southwest monsoon and the East Asian monsoon meet around LRGR, which forced the rainfall distribution and spatial change present longitudinal features along the river. The passing-obstructing effect of topography was obviously showed in the distribution of summer temperature over Nu-valley and Lancang-valley；such effect was only obvious on the spatial change of summer temperature around northwest part of LRGR,but was not obvious in the other region.