Six DNA components of Banana bunchy top virus (BBTV) were amplified by polymerase chain reaction (PCR) using total DNA from banana tissues having the typical BBTV symptoms as template. The sequence analysis indicated that the six fragments (1104 nt, 1067 nt, 1059 nt, 1045 nt, 1014 nt and 1081 nt) were all full-length components of BBTV. The viral sequences from different countries were compared. Results revealed that the sequence of component 1 was more conservative than other components, DNA1 of the Hainan isolate shared 95.4% homology with that of the Vietnam isolate, while sequences of both components 2 and 4 showed less homology. DNA2 of the Hainan isolate only shared 83% homology with that of the Guangzhou isolate. According to the results of the DNA1 sequence comparison, the BBTV Hainan isolate should belong to the Asian sub-group.