The title compound, [Mn(C8H5O3)(2)(C10H14N2O)(2)(H2O)(2)], contains one Mn-II atom lying on an inversion centre, two 4-formylbenzoate and two diethylnicotinamide ligands and two coordinated water molecules. All ligands are monodentate. The four O atoms around the Mn atom form a slightly distorted equatorial plane, while the distorted octahedral coordination is completed by the two N atoms in the axial positions. An intramolecular O-H center dot center dot center dot O hydrogen bond occurs in the complex. In the crystal structure, O-H center dot center dot center dot O hydrogen bonds link the molecules through an R-2(2)(16) ring motif, forming a one-dimensional chain along the a axis. The pi-pi contact between the pyridyl rings [centroid-centroid distance = 3.629 (2) angstrom] may further stabilize the structure.