The synthesis and characterization of the oxo-centered carboxylato-bridged trinuclear iron(III) complex, triaquahexakis(μ2-betaine)(μ3-oxo)triiron(III) perchlorate heptahydrate are described. X-ray crystallography shows that the FeIII atom in the complex has a slightly distorted octahedral geometry, coordinated by four oxygen atoms from different betaine ligands [Fe—;O = 2.009(3) ∼ 2.034(3) Å], one aqua ligand [Fe—O = 2.028(4) and 2.031(3) Å] and the central μ3-oxo atom [Fe—O = 1.917(2) and 1.917(3) Å]. The central oxygen is ideally coplanar with the plane of the three metal atoms. Magnetic susceptibility data (4–320 K) show the presence of an antiferromagnetic exchange interaction with a coupling constant of J = −20.2 cm−1.