A Gram-negative, aerobic, non-spore-forming, halophilic bacterial strain, NTU-104(T), was isolated from the Szutsao saltern in southern Taiwan, which was previously used as salt production field. The novel isolate grew optimally at 35-40 degrees C, at pH 7.5-8.0 and in the presence of 5 % (w/v) NaCl. The major fatty acids were C(16 : 0), C(18 : 1)omega9c, C(16 : 1)omega9c, C(12 : 0) 3-OH and C(12 : 0). The predominant quinone was Q-9. Phosphatidylglycerol, diphosphatidylglycerol and phosphatidylethanolamine were the predominant polar lipids. The DNA G+C content was 56.5 mol%. Phylogenetic analyses based on 16S rRNA gene sequences revealed the affiliation of the novel isolate to the genus Marinobacter. DNA-DNA hybridization results between strain NTU-104(T) and the type strains of the most closely related species, Marinobacter pelagius and Marinobacter koreensis, were 36.4 % and 33.2 %, respectively. On the basis of phenotypic, phylogenetic and genetic analyses, strain NTU-104(T) is considered to represent a novel species of the genus Marinobacter. The name Marinobacter szutsaonensis sp. nov. is proposed, with strain NTU-104(T) (=BCRC 17809(T)=CGMCC 1.7011(T)=JCM 15751(T)) as the type strain.