A bacterial strain, designated T20R-70T, was isolated from tomato rhizosphere soil collected in Yecheon-gun, Gyeongsangbuk-do in South Korea. Growth was observed within the ranges 10-40 °C (optimally at 28-30 °C), pH 7.0-8.0 (optimally at pH 7.0) and 0-1 % NaCl (optimally at 0 %). The 16S rRNA gene sequence showed the highest similarities with those of Lysobacter hankyongensis KTCe-2T (98.7 %), Lysobacter brunescens KCTC 12130T (98.0 %), 'Lysobacter daecheongensis' Dae08 (97.2 %) and Lysobacter oligotrophicus 107-E2T (97.1 %). The phylogenetic tree showed that strain T20R-70T formed a clade with Lysobacterhankyongensis KTCe-2T and Lysobacterbrunescens KCTC 12130T. The dominant fatty acids (>10 %) were iso-C15 : 0, iso-C16 : 0, iso-C17 : 1ω9c and summed feature 3 (including iso-C15 : 0 2-OH and/or iso-C16 : 1ω7c). The major polar lipids were phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylglycerol. The major respiratory quinone was Q-8. DNA-DNA hybridization data revealed that strain T20R-70T had a hybridization value of 42±4 % (mean±sd) to the most closely related species of the genus Lysobacter. The DNA G+C content was 63.0 mol%. The physiological, biochemical and chemotaxonomic data allowed the discrimination of the new isolate from its phylogenetic relatives. Strain T20R-70T is thus considered to be a representative of a novel species of the genus Lysobacter, for which the name Lysobactersolanacearum sp. nov. is proposed. The type strain is T20R-70T (=KACC 18656T=NBRC 111881T).