Abstract: There have been found 5 species of injurious mites in the mulberry plantations of Guangdong Province, (?) (Banks) and (?) Andre being the major onsis The changes in the water, ptotein and total amino adds content in the mulberry leaves attacked by (?) lation (Banks) are first reported in this paper. The absolute levels of the above-mentioned substances of the attacked leaves were greatly decreased, and thus the sericultural productivity was seriously affected. As to the studies on the control of both of the injurious mites in mulberry plantations in terms of harvesting methods and chemical measures, the top-clipping harvesting methods and the ordinary leaf-harvesting method had a different effect on the population density of the mites in the field;in respect to the depression ratio of the population and population trend index (I) value,in the assessment of the efficacy of several kinds of insecticides upon (?) (Banks), the results showed that lime sulphur mixture and Proparsits wen both effective in controlling the mites with low toodcity so the silkworms; they can be popularized in mulberry plantations.