Abstract: The data,vectorial capacity of Anopheles sinensis in the suburb of Jining city,ShandongProvince in 1975,in 1980-1984,and the average gland infection rate of Anopheles sinensis in-fected with Plasmodiuln vivax artificially, were calculated by using Macdonald formula(1957).The basic reproduction rates were 4.44,6.47 and 4.25 in the years 1975 ,1980 and1981,respectively.In 1982-1984,the rate was reduced to 0.69,0.41 and 0.1,respectively.Since 1982,the incidence rate of malaria in the areas was reduced by 80% annually, indicatingthat the malaria transmission had been decreased obviously.