Rice black-streaked dwarf disease(RBSDD) and rice stripe disease(RSD) are two important viral diseases occurring in rice growing areas along the Yellow River,which are both transmitted by small brown planthopper(SBPH).In order to clarify the relationship between SBPH and the incidence of viral diseases on different rice cultivars,this study surveyed quantities and viruliferous rates of SBPH on peak days during 5 years from 2014 to 2018 in Duliang,Kaifeng.And occurrence of RBSDD and RSD in common rice cultivars was counted and analyzed. It was found that effective inoculation quantities of SBPH carrying RBSDV were highest in the years of 2014 and 2016 with 1.948 4 million and 1.711 1 million per hectare,followed by the years of 2017 and 2015,and the minimum effective inoculation quantity of SBPH was obtained in the year of 2018. During the five years,occurrence of RBSDD was common,and the years of 2014 and 2016 witnessed more serious RBSDD,with disease rates of Huaidao 5 at 50.6% and 70.8%,respectively,which showed high susceptibility,and disease rates of Zhendao 88 at 30.6% and 29.3%,showing susceptibility and moderate susceptibility,respectively.Disease rates of RBSDD were less in the years of 2015 and 2017,and that in the year of 2018 was the lowest. However,occurrence of RSD was sporadic all through the five years.Disease rates of RBSDD varied in different rice cultivars,and those in the same rice cultivar also varied during different years. Results show that effective inoculation quantities of SBPH,which are decided by quantity of SBPH and its viruliferous rates on peak days,have an important effect on the occurrence of rice viral diseases.