During a study aiming at isolation and genomic characterization of non-pathogenic fish symbionts, strain F-328(T) was isolated from skin mucus of healthy-seeming rainbow trout (Oncorhynchus mykiss) and subjected to polyphasic characterization, including a comprehensive genome analysis. Strain F-328(T) was Gram stain negative, none-gliding, strictly aerobic, and rod shaped. The 16S rRNA gene sequence of strain F-328(T) exhibited the highest level of identity (98.9%) with F. turcicum F-339(T). The major fatty acids were iso-C-15:0, C-15:1 omega 6c, and summed feature 3 (C-16:1 omega 7c, C-16:1 omega 6c). The polar lipid profile consisted mainly of phosphatidylethanolamine and aminolipids, while the predominant menaquinone was MK-6. The DNA G + C content and genome size of the strain were 35.3% and 3.4 Mb, respectively. Strain F-328(T) shows 93.8% average nucleotide identity and 53% digital DNA-DNA hybridization identity with the closest type strain F. turcicum F-339(T). In addition, strain F-328(T) was found to carry antimicrobial resistance genes, which confer resistance to several antimicrobials, including aminoglycoside, macrolides, and streptogramin. Differential phenotypic properties, together with the phylogenetic inference, demonstrate that strain F-328(T) should be classified as a novel species of the genus Flavobacterium for which the name Flavobacterium erciyesense sp. nov. is proposed, with F-328(T) as the type strain (= JCM 34201(T) = KCTC 82261(T)).