The title compound, {[U(C(12)H(14)O(4))O(2)(H(2)O)] x H(2)O}(n), is the first actinide complex featuring adamantanecarboxylate ligands. The metal ion possesses a pentagonal-bipyramidal UO(7) coordination involving two axial oxide ligands [U-O = 1.732 (5) and 1.764 (5) A] and five equatorial O atoms [U-O = 2.259 (5)-2.494 (4) A] of aqua and carboxylate ligands. The latter display pseudo-chelating and bridging coordination modes of the carboxylate groups that are responsible for the generation of the centrosymmetric discrete uranium-carboxylate [UO(2)(mu-RCOO)(2)UO(2)] dimers [U...U = 5.5130 (5) A] and their connection into one-dimensional chains. Hydrogen bonding involving two coordinated and two solvent water molecules [O...O = 2.719 (7)-2.872 (7) A] yields centrosymmetric (H(2)O)(4) ensembles and provides noncovalent linkage between the coordination chains to generate a three-dimensional network structure.