In the title complex, [Mn(C(8)H(4)O(7)S)(C(12)H(8)N(2))(2)], the Mn(II) atom is chelated by one 4-carb-oxy-2-sulfonato-benzoate anion and two phenathroline (phen) ligands in a distorted octa-hedral MnN(4)O(2) geometry. The benzene ring of the 4-carb-oxy-2-sulfonato-benzoate anion is twisted with respect to the two phen ring systems at dihedral angles of 66.38 (9) and 53.56 (9)°. In the crystal, inter-molecular O-H⋯O and C-H⋯O hydrogen bonding links the mol-ecules into chains running parallel to [100]. Inter-molecular π-π stacking is also observed between parallel phen ring systems, the face-to-face distance being 3.432 (6) Å.