In the crystal structure of the title compound, [KV(C(10)H(13)N(2)O(8))O(H(2)O)(3)](n), the V(IV) ion adopts a distorted octa-hedral geometry, coordinated by one oxide group, two N and three carboxylate O atoms from the same N'-carboxy-methyl-ethyl-ene-diamine-N,N,N'-triacetate (HEDTA) ligand. The potassium ion is hepta-coordinated by two water mol-ecules, two bridging water mol-ecules and three carboxylate O atoms from three neighbouring HEDTA ligands. The HEDTA ligands and some of the water mol-ecules act as bridges, linking the compound into a three-dimensional architecture via 2(1) screw, c-glide, translation and inversion symmetry operators. Meanwhile, three types of O-H⋯O hydrogen bonds provide an additional stabilization of the three-dimensional architecture.