The taxonomic position of a rhizosphere soil isolate, designated strain SR8.15T, was determined by using a polyphasic approach. Phylogenetic analysis based on an almost-complete 16S rRNA gene sequence of the strain showed that it formed a well-separated sub-branch within the radiation encompassing the genus Saccharopolyspora. Highest levels of 16S rRNA gene sequence similarity were found between strain SR8.15T and Saccharopolyspora shandongensis CGMCC 4.3530T (98.9%) and Saccharopolyspora spinosa DSM 44228T (98.5%). However, these strains shared low levels of DNA-DNA relatedness (<26%). Strain SR8.15T had chemical characteristics consistent with its classification in the genus Saccharopolyspora. It contained meso-diaminopimelic acid as the diagnostic diamino acid. Whole-cell hydrolysates contained arabinose and galactose. The diagnostic phospholipids were phosphatidylcholine, phosphatidylglycerol and phosphatidylinositol. The main menaquinone was MK-9(H4). No mycolic acid was detected. The predominant cellular fatty acid was iso-C16:0. The G+C content of the genomic DNA of strain SR8.15T was 70.3 mol%. Strain SR8.15T had a phenotypic profile that readily distinguished it from recognized representatives of the genus Saccharopolyspora. It is evident from its combined genotypic and phenotypic properties that strain SR8.15T represents a novel species of the genus Saccharopolyspora, for which the name Saccharopolyspora phatthalungensis sp. nov. is proposed. The type strain is SR8.15T (=TISTR 1921T=BCC 35844T=NRRL B-24798T).