Virus isolate YN72 was obtained from Jimsonweed (Datura stramonium L.) showing vein thickening, leaf curling and stunt symptoms in Dali, Yunnan province. The complete nucleotide sequence of DNA-A was determined, it contained 2 739 nucleotides. Comparisons showed that DNA-A of YN72 had the highest sequence identity (93.4%) with that of Tomato yellow leaf curl China virus (TYLCCNV) isolate Y43, and 92.9% with that of TYLCCNV tobacco isolate Y5, while less than 90% identities were found when compared with other begomoviruses isolated in Asian. It was concluded that isolate YN72 infecting Datura stramonium L. was one of TYLCCNV isolates. Satellite DNA molecule' YN72β was found to be associated with YN72 using the primers beta01 and beta02. YN72β consisted of 1 335 nucleotides, with a functional ORF (C1) in complementary-sense DNA. It had 99.8% and 99.3% sequence identities with Beanβ and Y297β associated with TYLCCNV, respectively, and lower than 80.6% sequence identities were found with other reported satellite DNA molecules. Relationship dendrograms showed that satellite DNAβ molecules were coevolved with their help begomoviruses.