Abstract: Under the system of rice intensification,the root activity,N content of plant in all growing stage,the filling rate and the chlorophyll content in ripening stage were studied by using the conventional rice variety "Yuexinzhan" and hybrid rice combination "Tianyou372".The result showed that the root activity in all growing stage,the N content and filling rate in late growing stage,chlorophyll content in ripening stage were increased,and the leaf senescence was delayed,therefore,the grain setting rate and grain yield were increased under the system of rice intensification.