A novel yellow-pigmented, agarolytic bacterial strain, designated ZC1T, was isolated from the surface of the marine red alga Porphyra haitanensis collected near Nan Ao Island, Guangdong province, China. The isolate was Gram-stain-negative, strictly aerobic and rod-shaped and displayed β-galactosidase, alkaline phosphatase, catalase and oxidase activities. The predominant cellular fatty acids were iso-C15:0, summed feature 3 (comprising C16:1ω7c and/or iso-C15:0 2-OH) and iso-C17:0 3-OH. The major menaquinone was menaquinone 6 (MK-6). The DNA G+C content was 32.8 mol%. Phylogenetic analysis of the 16S rRNA gene sequence revealed that strain ZC1T was closely related to members of the genus Aquimarina in the family Flavobacteriaceae, phylum Bacteroidetes. Based on phylogenetic and phenotypic evidence, strain ZC1T (=CCTCC AB 2010229T=NBRC 107695T) represents the type strain of a novel species in the genus Aquimarina, for which the name Aquimarina agarilytica sp. nov. is proposed.