Phenotypic and genomic analyses were performed to characterize two novel species, H23M54T and AMA3305T, isolated from the faeces of the Oriental stork (Ciconia boyciana) and the cinereous vulture (Aegypius monachus), respectively. Strains H23M54T and AMA3305T showed the highest similarities of 16S rRNA gene sequences and complete genome sequences with Ornithinimicrobium cavernae CFH 30183T (98.5% of 16S rRNA gene sequence similarity and 82.1% of average nucleotide identity, ANI) and O. pekingense DSM 21552T (98.5% of 16S rRNA gene sequence similarity and 82.3% of ANI), respectively. Both strains were Gram-stain-positive, obligate aerobes, non-motile, non-spore-forming, and coccoid- and rodshaped. Strain H23M54T grew optimally at 25–30°C and pH 8.0 and in the presence of 1.5–2% (wt/vol) NaCl, while strain AMA3305T grew optimally at 30°C and pH 7.0 and in the presence of 1–3% (wt/vol) NaCl. Both strains had iso-C15:0, iso- C16:0, and summed feature 9 (iso-C17:1 ω9c and/or C16:0 10- methyl) as major cellular fatty acids. MK-8 (H4) was identified as the primary respiratory quinone in both strains. Strains H23M54T and AMA3305T possessed diphosphatidylglycerol and phosphatidylglycerol as major polar lipids. Moreover, strains H23M54T and AMA3305T commonly contained ribose and glucose as major sugars and L-ornithine, L-alanine, glycine, and aspartic acid as major amino acids. The polyphasic taxonomic data indicate that strains H23M54T and AMA3305T represent novel species of the genus Ornithinimicrobium. We propose the names Ornithinimicrobium ciconiae sp. nov. and Ornithinimicrobium avium sp. nov. for strains H23M54T (= KCTC 49151T = JCM 33221T) and AMA3305T (= KCTC 49180T = JCM 32873T), respectively.