The complete genomic sequence of cassava common mosaic virus isolate Linggao (CsCMV-LG) was determined from cassava (Manihot esculenta Crantz) with mild foliar mosaic symptom in Hainan Province, China. Excluding the poly(A) tail, the CsCMV-LG genome (GenBank accession No. MT038420) is 6374 nucleotides (nts) in length, with five major open reading frames encoding a 1450-amino acids (aa) RNA-dependent RNA polymerase (RdRp), three triple gene block (TGB) proteins (231-aa, 110-aa and 95-aa), and a 229-aa coat protein (CP). Phylogenetic analysis based on the complete sequence indicated that CsCMV-LG is closely related to CsCMV-Brazilian which belongs to the genus Potexvirus, but the sequence identity shared only 88.0%. Notablely, the CsCMV-LG can also infect tobacco (Nicotiana benthamiana) in laboratory through rub inoculation causing chlorosis and malformation symptoms 15 days post inoculation (dpi). The study extends genome sequence and genetic diversity of CsCMV and provides an important basis for the virus detection in cassava.