Using tDNA-PCR, the type strain CCM 7198T (<--CIP 107470T <--17A04T) of Acinetobacter grimontii was found to be indistinguishable from Acinetobacter junii strains. Therefore, the phenotypic properties, amplified fragment length polymorphism (AFLP) patterns and 16S rRNA and rpoB gene sequences of the type strain of A. grimontii (CCM 7198T) were determined. We found that the strain used l-arginine and l-glutamate, in contrast to the original description and in accordance with the phenotypic properties of A. junii. By AFLP analysis, A. grimontii CCM 7198T clustered at 50.2 % with a set of A. junii strains previously identified by DNA-DNA hybridization, which is in accordance with the previously established intraspecies values of this technique. Sequence similarity of the 16S rRNA gene between the type strains of the two species was found to be 99.9 %. Finally, DNA-DNA relatedness between the type strains of A. junii and A. grimontii was redetermined and was found to be 85 %. These findings were corroborated for a second representative of the A. grimontii type strain, DSM 14968T. These data confirm that Acinetobacter grimontii is a later heterotypic synonym of Acinetobacter junii.