Spider mites are important agricultural pests causing significant damage to commercial crops. In recent years, these pests have greatly hampered agricultural development in China. With support from the Chinese Ministry of Agriculture’s Special Fund for AgroScientific Research in the Public Interest, we conducted a series of studies of spider mites. Population fluctuations of spider mites were investigated in orchards in the northeastern and northern China, and in vegetable fields in the north. The population structures of the carmine spider mite, the twospotted spider mite and the citrus red mite were investigated. Important progress has been made in research on the effects of Wolbachia and Cardinium infection on the fitness of populations of the twospotted spider mite and the carmine spider mite. Significant advances have also been obtained in biocontrol and chemical control of these pests and three integrated control systems established. The total area in which integrated control has been proven effective has now reached 2 000 hm2.