Tobacco bushy top disease was a severe tobacco disease in western Yunnan Province, China. It broke out in the rural areas of Baoshan in 1993 first time. From 1993 to 1998, 50 000 ha of flue- cured tobacco and some oriental tobacco were affected with direct economic losses of about 25 million U.S. dollars. The disease was falsely regarded as having a phytoplasma etiology before 1999. Comparative studies on symptomoloy, host range, transmission means indicated that it is tobacco bushy top disease which has been reported in sub- Saharan Africa. Tobacco bushy top disease was caused by tobacco bushy top virus and tobacco vein distorting virus. The complete nucleotide sequence of a Chinese isolate of tobacco bushy top virus was determined. The results indicated that tobacco bushy top virus should be listed as a definitive member of the genus Umbravirus. Partial sequence of the genome of tobacco vein distorting virus was obtained, including partial RNA- dependent RNA polymerase, coat protein and movement protein. The results indicated that tobacco vein distorting virus was a definitive member of the family Luteoviridae. A satellite- like RNA of tobacco bushy top virus was discovered and its partial sequence obtained. With the above - mentioned sequence data, RT- PCR primers were designed and used for molecular detection of tobacco bushy top disease. Integrated pest management strategy based on control of vector aphids was devised according to the research results of disease transmission manner and epidemiology.The control strategy was applied to over 80 000 ha of tobacco plantation and reached a big success.