Abstract:In the early of 1960‘s, rice black-streaked dwarf disease and maize rough dwarf disease had been found separately in the rice field of Yuyao in Zhejiang Province and in the maize field of Baoding in Hebei Province of China. They have prevailed twice during past forty years. Through the studies of control methods of these diseases, their development rules have been known and the technique to control them has also been practiced in the disease-prone area. Afterwards these diseases were under controlled. Since the late of 1980‘s, rice black-streaked dwarf disease has only occurred in the local districts of east-China and maize rough dwarf disease has increasingly become epidemic in the 13 provinces of China. According to the similar reports about their viral shapes, host ranges and symptoms, vectors and transmission properties, the pathogenies of these two diseases were suspected of a same virus. During recent ten years, the researches on rice black-streaked dwarf disease and maize rough dwarf disease with biological and molecular biological methods have showed that the pathogenies of these two diseases both are belonging to rice black-streaked dwarf virus (RBSDV).