The complete RNA genome from Cucumber green mottle mosaic virus (CGMMV) (Alm08), collected during 2009 in cucumber crops located in Spain, was found to be 6,422 nucleotides long. The nucleotide sequence shared the highest identity with isolates from Russia (GQ495274, GQ495275, FJ848666) as do nucleotide sequences of partial CP and MP genes described in Spain since 2005. All the partial genome sequences including RdRp, CP, and MP from 26 isolates collected from 2013 to 2015 in the southeast of Spain, and from seven isolates of other parts of the world, suggest that they grouped in two major clusters: one cluster (I) included 14 isolates collected between 2013 and 2014, and also reference isolates from France, the Netherlands, and Uzbekistan. A second cluster (II) grouped 12 isolates, which were mostly collected in 2015 together with those from Japan, South Korea, and Canada. For the first time, CGMMV isolates of different geographical origin were found coinfecting the same crop and territory. A host range study revealed that representative isolates of cluster II, but not from cluster I, produced local lesions in Chenopodium amaranticolor. RT-PCR using a common primer pair for CGMMV followed by restriction enzyme analysis with KpnI allowed distinguishing cluster I from II CGMMV isolates.