Tobacco curly shoot virus (TbCSV), a monopartite begomovirus (genus Begomovirus, family Geminiviridae), is a serious threat to many crops and weeds in China and India. In this study, a begomovirus disease complex was identified from a watermelon sample displaying severe leaf curling and yellowing symptoms. The genome of this TbCSV isolate Y3560 contained 2,744 nucleotides (nt) and shared 97.9% identity with the TbCSV YN4519 isolate. The complete nucleotide sequence of the betasatellite DNA molecule associated to isolate Y3560 contained 1,342 nt and shared 91.0% sequence identity with the Tomato yellow leaf curl China virus betasatellite isolate TYLCCNB-Y319. The nucleotide sequence of the alphasatellite contained 1,372 nt and shared the highest levels of identity (94.0%) with Tobacco curly shoot virus associated DNA1 (TbCSA). This is the first report of a monopartite begomovirus and associated satellites from watermelon.