Two different polysaccharides were obtained by mild acid degradation of the lipopolysaccharide of Rahnella aquatilis 33071(T). These were studied by sugar and methylation analyses along with 1D and 2D (1)H and (13)C NMR spectroscopy. The following structures were established for the polysaccharides: -->4)-alpha-D-Rhap-(1-->3)-alpha-D-Rhap-(1-->3)beta-D-Galp-(1-->3)-alpha-D-Manp-(1-->2)-alpha-D-Manp-(1--> beta-D-Glcp-(1-->3)-alpha-D-galp-(1-->4)-alpha-D-GlcpA-(1-->2). The former structure is new, whereas the latter has been reported earlier as the structure of the O-specific polysaccharide of R. aquatilis 95 U003 (Zdorovenko, E. L.; Varbanets, L. D.; Zatonsky, G. V.; Kachala, V. V.; Zdorovenko, G. M.; Shashkov, A. S.; Knirel, Y. A. Carbohydr. Res.2008, 343, 2494-2497).