Tetranuclear manganese complexes have received much attention as model complexes of tetranuclear manganese center of oxygen-evolving center (OEC) since such system was discovered in the active site of OEC of photosystem II [1,2]. We have engaged in chemistry of manganese complexes, paying attention to their magnetic properties with a variety of unpaired electrons depending on the oxidation state of manganese. So far, we synthesized some manganese complexes by the use of dinucleating and polydentate ligands [1,2]. Gorun et al. reported that tetranuclear and hexadecanuclear manganese complexes can be isolated by reaction of 1,3-diamino-2-hydroxypropane-N,N’,N”,N”’-tetraacetic acid (H5dhpta) and manganese salt [3,4]. In this study, we examined reaction of H5dhpta with manganese salt by changing counter ion in the hope of obtaining new polynuclear manganese complexes. We isolated a similar compound to Gorun’s tetranuclear manganese complex. Temperature dependence of magnetic susceptibilities of the compound (4.5—300 K) showed an antiferromagnetic interaction. Herein, we report on the crystal structure and magnetic property of this compound.