A Gram-negative, non-motile, non-spore-forming, halophilic rod, designated JPCCMB0017(T), was isolated from a marine sediment of the coastal area of Okinawa, Japan. The isolate formed orange-red colonies on marine agar. Bacteriochlorophyll α was absent and sphingoglycolipid 1 and other carotenoids, including astaxanthin, adonixanthin and zeaxanthin, were present. Ubiquinone-10 (Q-10) was the main respiratory quinone and C(18:1)ω7c was the major cellular fatty acid. The G+C content of DNA was 59.1 mol%. Phylogenetic analysis based on 16S rRNA gene sequencing revealed that the isolate was a member of the genus Altererythrobacter in the family Erythrobacteraceae. Strain JPCCMB0017(T) exhibited 96.8% 16S rRNA gene sequence similarity with Altererythrobacter marinus H32(T). Unlike other members of the genus Altererythrobacter, strain JPCCMB0017(T) reduced nitrate. On the basis of genotypic and phenotypic data, a novel species is proposed to accommodate this isolate, with the name Altererythrobacter ishigakiensis sp. nov. The type strain is JPCCMB0017(T) (= NITE-AP48(T)= ATCC BAA-2084(T)=NBRC 107699(T)).